0et8 i s of 250mm MORTAR

Interrogation Report of ld Lt. MATSUO, MASAM.I

Prepared by G-2 Section, 27th Inf, Div.

NOT ~ · All information container herein is derived from POW interrogation and must be evaluated accordingly. C 0 N F I D E N T I A L

HEADtlUARTERS 27TH INFiu~TRY DIVISION - b. • .P.O. 27 21 August 1944 POW INTERROGATION REPORT

Interrogated by Language Team, 27th Inf. Div 10, 11, 18 August, 1944

Name: 1~TSUO, Masami Rank: lst Lt. Duties: Ordnance Officer and CO Command Section of Bn Hq. Age; 35 Unit: 14th Independent Mortar B&ttalion, Code No. 12586. Bn CO: JINNOUCHI, Captain Education: Attended mis~ion school (11 Americans on faculty - believes all were exchanged). Religion: Catholic POW understands English slightly. C.::. ptured on SAIPAN Island by the 27th Infantry Division. A. HISri'ORY OF POVV:

1954 - Graduated from misbion school at FUKUOKA KEN. (School is a junior college). 1934- Passed examination for officer candidate and attended o.c.s., {six months) 1934 - Graduated from officer candidate school; served two months as probationary officer. 1935 - Assigned to "Port Arthur Heavy Field Arty Regt" at Port Arthur, ,J!ANCHURIA. 1936 - Attended field artillery gunnery school in JAPAN. 1956 - Relieved from active duty - s~ c nt his time taking care of father's lands. 19~ . -Recalled into service- reassigned to Port Arthur Heavy Field Arty Rcgt. 1957 - Attended motor und electrical school in IISINKING, M..4.NCHURIA. 1937 - 1940 - Took part in four campaigns of the China Incident. 1940 - Active service in the NONIOHAN Bord c_ r Incident against the Russians as lst Lt. in command of: a 11 COminand Battery" of a regi­ ment of 155mrn guns which wc, s part of the KWANTUNG (KANTO) 6th Army. POW st&tes 'that he killed four Russians with his sword. Incident ~nded with "victory for both sides:· as an agreement was reached bctwe E.. n the t no nations." 1940 - Released from active service - remained in l~NCHURIA uorking in the statistic~l department of the l~CHURIAN Railway Company. POW ap.i-'arcntly has considerable knowledge about the resources of i'liANCHURIA because he says his duties were to mcke estimates of coal and other nat\~al resources. 1943 - Returned to Japan - lived with his father. 20 Apr 1944 - Recalled into active service. Assigned to SASEBO Hecvy Artillery Unit (240mm HOW) and immediately thereafter to the 14th Independent Mortar Bn which vlas "- l'eing formed of men from the SASEBO Artillery Unit and other trained artillerymen.

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.. , . .: ',.').."' ' . _ r~:~~ · · .~ ~4 • -: • ~ ·; C 0 N F I D E N T I A L B• DETAIL8 OF ,VlOVE TO SAIP AN. POW sailed from YOKOHA111A May 29 in a convoy of seven transports es­ corted by five corvettes. Over a period of three days (June 5,6,7), five of the transports were sunk by our submarines. POW 1 s unit was on the HABUL f~U (6000 tons) which was the last ship sunk. Most of the personnel of the mortar battalion were picked up by one of the escorts and it lost only about fifty men. POW believes that about one thPusand men from the entire convoy were lost.

POW's tinit was sup~osed to go to PALAU but because ·of the ships lost enrouta, it was landed at GARAPAN. However, all their equipment had been lost and they had only twenty rifles. Grenades enough for each man were issued later. C. ORGANIZATION OF INDEPENDENT MORTaR BATTALION,

Attached hereto is a translation of the table of organization as written by the POW. This battalion.was placed under the direct command of the 31st Army when it reach SAIPAN. D. DETAILS OF 250mm MORTAR (KYUHO) (No model number known).

According to POW, this mortar h~s been used only once by the Japanese. This was at SINGAPORE when one mortar w~s set up in a rubber tree grove and used to fire three rounds on BUKIT~~ Hill. This hill dominated the prin­ cipal airfield and according to the Japanese story, it was taken largely be­ e ause of the effect of the three rounds fired by this mortar. The Japs intended to bring up more mortars to fire on the hillbut difficulty of transportation and the need for haste, gave them opportunity to get only one emplaced. However, this was reported as sufficient and give an impressi0n of the Japanese idea. of the effectiveness of th~s weapon. At least two battalions of these mortur3 were slated for the South Seas the 14th to PALAU and the 17th to GUAM but both of thP-se landed at SAIPAN with no equipment because of submarine activity. POW believes that the mortars were to be set up in fixed positions and laid on the best landing areas. He said that only about 10 rounds C('Uld be firf3d after the mortar had been emplaced because the concussion from 10 rounds would throw it out of line. However, he believes that it would be possible to fire only two or three rounds before the mortar W<'uld be definitely located and subjected to concentrations of enemy fires. The location of the mortar is very easy to ascertain because the projectile is so large and its velocity ~o slow. In addition, the blast when the weapon is fired would reveal the position t0 an observer very easily. Surplus mortal'S are carried as replacements by the battalion. The primary use of the mortar is against persolll1el but since t~ero is also a delayed action fuze, it can be used against emplacements. The cc'ncussion when the piece is fired is so great that the men manning the ~m ~ust remain in dugouts nearby or at least 500 meters away if above grou..11d. C 0 N F I D E N T I A L , - 2 -

Color Control Patches Green Yellow Red Magenta White C 0 N F I D E N T I A L Technical Details; {See diagram "A". attached) Maximum range: 1300 meters Effective range: 800-1100 meters. Radius of burst: 500 meters. Total weight (tube and base plate): 80 kg (can be carried by 4 men). Diameter of bore: 250mm Length of tube: 1.2 meters. Diameter of projectile: 520mm. Weight of projectile: 272 kg (approx) - The projectile is divided into three sections which are fitted together before the projectile is fired. Fuze: Screws in nose - point detonating or delay. Powder charge: bags - 200mm in diameter, 15mm thick, 1 charge is used for each 100 yards of range {approx). Bags contain an explosive which is similar to that used in "magnetic" mines. It is primarily picric acid. POW wrote out the following name for it: .::!±_ , -t-~ / .. \-:H ~ .~ / ->- - / It:/ . \TI · ff:f~ 1 _y_ 'KI?!i J IJ -ft ~ feY, "' ...._.;T, . Ill\ Jr-., ;;;1, Booster Charge: 3 11 in diameter and 15mm thick. Length of projectile: 1.7 - 1.8 meters . Firing mechanism: The mortar may be fired by hand or electrically. If fired by hand, a firing device is screwed into the tube (See diagram "A"). This device is operated by pulling the head with a lanyard. Friction is caused by this, igniting a powder train, which sets off a booster charge, which in turn explodes the powder bags. In order th t it be fired electrically, a wire is attached to a ter­ minal fixed in the side of tho tube. A plunger, connected to the end of the wire, is used to set off the charge. The mortar is usually fired in this manner when the range is short because the burst of the projectile would be dangerous to the mortar gttnners. Vfuen fired electrically, 4 mortars are ordinarily fired at the same time by the officer commanding the platoon. The mortar is emplaced by digging a hole in the ground (See diagram 11 B"). A firm base is usually built up of timbers placed crossways to each other,although the mortar can be set on the gt'ound in the hole. The base plate is bolted to the timbers at an angle of 45 degrees,

The tube has a flange around its base which is bolted to the base plate. The bolts fit through slots in the base plate so that the deflection and range settings can be changed slightly. There are graduations on the base plate to aid in making these changes. The maximum change that can be made according to POW is 200mm. There is no way of changing the range or deflection setting once the tube is bolted to the base except by loosening the bolts and sliding the tube in the desired direction. If a change of more than 200mm is necessary, the base plate must be moved, necessitating a change in ~he foundation,

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~ Color Control Patches Green Yellow Red Magenta White C 0 N F I D E N T I A L E. POW's UNIT DURING COMBAT.

Until July 6th, it was in the vicinity of f~lATUISA (TA 268). Its mis­ sion ws. s to e.ct as reL-r guard for the forces defending the northern half of the island. In addition, they acted in the nature of MP•s in a strag­ gler line directing scattered personnel Dack to their organization. They also were used to place sea mines on the roads in the north.

At 1800, 6 July, orders came fromLt. General SAITO, who was then near TA 261 J for an all out attack to be launched in three groups; one group was to go south along the western railway, a second from MATANSA (TA 267) down the center of the island, and the third to go from i~TANSA south, thence through KARABERRA PASS to the east and south to TARAHOHO, DONNAY and CHARAN KANOA. The mortar battalion was in the group going south along the railroad, and was ordered to move in column of platoons with CH.ARAN KANOA as the ob­ jective. POW can give no estimate of total strength taking part in the counterattack but knows that in his battalion alone, there were about six hundred soldiers. He was assigned the duty of bringing up the rear with the battalion headquarters unit. The CO led the battalion in the attack and is presumed to have been killed. POW said that after the attack Wc.s well under way, daybreak came so he retreated to the airfield with thirty of his men.

An interesting statement made by the POW is th..t orders for an attack od' this kind (GYOKU-SAI "Die in honor") shc·uld come from the higher command in Japan as it is the last supreme effort when all arc supposed to die. The POW states that he and many others believe that the order for this attack actually came directly from Lt. General SAITO. The r eason for this belief is thatGeneral SAITO was notorious for his short temper and haste in action. F. DETAILS OF CAPTURE. From July 15 to August 3, POW hi d in the vicinity of TA 275 Q. August 3 to August 7, 11 11 11 11 TA 286 R. 11 11 August 7 to August 9, " " TA 281 M.

On 9 August, he vms sleeping with another officer when our troops fired on th0m. ':'he other officer committed suicide but the POW became unconscioue from r.n old wound in his right leg an•:l w&s captured. G. U.S. WEAPONS AND PREP il.RATION.

POW considered navnl gunfire our most fearoome weapon . However, he said the moat effective weapon was our artillery. He is an artilleryman and says he can distinguish naval gunfire from artillery by the size of the fragments. Every movement on the part of their troops brought fires on them. He thought the aerial bombardment was very ineffective.

'fhroughout the questioning, the 1/20,000 target area map was used to locate positions and POW was amazed at the detail of the map and thought it must have been prepared after the island was secured. C 0 N F I D E N T I A L _ . 4 -

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H. PO\fl s OJ? INION OF U.S . DEFICIENCIES.

1. POW admired our fire power greatly but felt that we depended too much on it although he was envious of it. He believes th~::.t manyan oppor­ tunity to advance was lost because we wasted time in firing excessive a­ mounts of ammunition in preparation fires into areas wheTe the enemy is very weak. In addition, he said that we place so much dependence on fire power that when our troops first came north, they fired large amounts of am­ munition into caves and woods but made no effort to enter the caves or search the woods. He SB.id Japanese soldiers who are not dependent on fire power would have gone right into the caves and forests. L.:J.ter, this deficiency was corrected by our men while mopping up.

2. POW criticized the failure of our tanks to advance with the infantry. He stated thc.t they fired from too great a range and that they would have been much more valuable if they advanced closer to the enemy. 5. He criticized what he termed lack of coordination between our units stating some some units advanced too rapidly leaving others in the rear thereby creating gaps in the U.S. lines. POW had not seen this but stated that this had been a subject·of discussion at the tactical headquarters. He heard about it there in a converaation with a major on the staff.

4. Before ht came to SAIPAN, POW w~s of the opinion that the Americans could not fight and that we considered "war as a sport." Now he says all his previous conclusions are erroneous.

· I... ~· EL\lENfY INTELLIGENCE.

POW said that as far as he knew, our landing was a complete surprise and that it was not expected until' August. In fact when our fleet appeo.red, POW thought it was simply another raid. When questioned as to how much information is given to Japanese soldiers concerning u.s. forces, POW stated that officers are given pamphlets and manuals. They are in the habit of discussing these among themselves but do not tell the enlisted men anything contained in these brochures. The enlisted men are told only how to fight but are not given any instruction in our tactics or other information about us.

J. J AfANESE TrtEAT!·tiENT OF AiJi:E,RICAN ·POVv t s.

POW stated trmt he had once visited a small POW camp in YOKOH&~ where about 10 Americans were confined v1i th some British prisoners. All of these prisoners appeared healthy and happy. In fact, POW said that from nii:f 'ob..:· .. serva tions, it must be an Amei·ican characteristic to be happy anywhere and to make the best of any situation.

With regard to food, the statement was made by POW that 11 funericans ea; a lot of bread - Japanese don't eat much of that and food is scarce but the Americans are given enough de~pite the fact that bread and milk are usually only given to Japanese sick." He als.o said tha.t officers do not i\ork unless C 0 N F I D E N T I A L 5

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Green Yellow Red Magenta White C 0 N F I D E N T I A L they care to and that enlisted men work under the direction of their own NCO •s. Most of the prisoners are engaged in mechanical v:ork because "all Americans seem so adept at this," and the Japanese are short of such skilled labor.

It had been announced in the Japanese press that some of the fliers from the Doolittle raid, who landed in Japan, were beheaded. The reason stated for this was that they had bombed schools and hospitals. POW had never heard of or seen any mistreatment of American POW's by the Japs.

When questioned as to the source of the belief by all Japanese mili­ tary that if they are captured they will be tortured and killed, POW said he recognized its prevalency but did not know the source. Officers do not tell the men this but the belief spreads like all rumors. K. ORGANIZATION.

POW was in the Port Arth~ Heavy Field Arty Regt. He stated that in ;'i!ANCHURIA , FA training regiments are divided into Class A, B, or C, units depending on the nmnber of guns. POW was in a Class C organization which had 8 guns (2 batteries). Class B units have 16 and Class A, 24. These types of units are for training only. When ready for combat, three Class C units may be combined or a Class B and C or any combination so that a combat regiment consists of 6 batteries of 24 guns.

The armament of POW • s organization in 1VlANCHURIA vms l55mm guns v;hich were tractor drawn. POW stated the maximum range of these guns is 28000 ineters and the eifective range 17000 - 20000 meters, He stuck to this story although the range seems excessive. L. PROPAGANDA, ETC.

l. POW felt that the leaflets had good effect but t hought more should have been dropped . He, as have all POW's questioned, stated that we should say little if anything about giving food and shelter because to the Japanese readers, it appears as if we consider them as animals. He heard the public address broadcast prepared by G-2, this headquarters, ~nd thought very highly of it.

Points that should he stressed in all propaganda are:

a. Atrocity stories are untrue.

b. It is more patriotic for soldiers and ~ivilians to live for the reconstruction of Japan than to die. c. Japan is no\f fighting the most powerful nation in the world - a nation v:hich can fight successfully on three fronts. We have taken many pri­ soners· and are continuing to capture Japanese soldiers in large numbers. As we advance westward, the number of prisoner s will increase. Japan is a civi­ lized nation and after the war is over, she must change her present policy and permit POW•s to return as respectable citizens, because of the large numbers involved. C 0 N F I D E N T I A L

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~::~0 ;..... ~ .:·~. . < C 0 N F I D E N T I A L d. The utter hopelessness of the Jap position and that defeat is inevitable. 2. Insofar as political activity is c

b. The middle-of-the-road group.

c. A smaller gr,>up who favor the American vvay of life but who will probably remain outwardly loyal to Japan. Our propaganda must be directed to c

POW stated th~t in his opinion, before the war, 50% of the Japanese people -yere symphatetic to America. He could give no estimate of the per­ centage at present time but believed it vm.s fairly large. In fact, he said that this large munber of "pro-Americans" in Japan can be her "weak poi~t" at the time of the invasion of Japan. He also said that 11 Tojo's Spirit" presses these people down at present and they can offer no active assistance to the u.s. POW said we should not think that Tojo is respondible for this war but rather that Tojo was merelythe instrumentality 0f the military clique. M. INVASION OF JAPAN.

POW stated that he believed the best place to invade Japan would be at TOKYO itself. He was told that he was probably saying this just to lead us into a trap. After a moment t s th<>ught, his answer to this was "Probably your casualties in planes, men and tunks will be greater there and greater than Japan's. However, the spiritual effect of such a ianding on the Japa~ nese people will be worth the losses. Results of the battle will be in our favor but the war situation in yours. The capture of TOKYO will break the spirit of the people." (Note: All POW•a continually speak of "spiritual" breakdown, etc., of the Japanese. We might stress this to our advantage in our propaganda. N. JAPAN VS RUSSIA.

POW feels that Russia· will eventually declare war on Japan ;vhcn it is obviously to her advantage. This should be SOi~1etime after we land in China and the outcome of the fighting there is definite. Apparently from POW's statements, the Jp ~ p,~~se hate the Russians more than the other allied nations. This is~ eep rooted feeling which has been instilled over a long period of years and POW felt that the feeling is mutual. POW did say when

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zt~· · · · "·- ~~;! ,;,.~-~~. /; . ·.: ------C 0 N F I D E N T I a 1 we get to China, t ghting will be considerably different from SAIPAN as the Japanese army is better there and can take advantage of their mo­ bility and equipment. 0. RELIGION IN JAPAN. POW stated that there is freedom of religion in Japan. He himself is a Catholic and aa aurh received no mistreatment. The chief religions in Japan are Bhuddism, Shintoism, end Christianity. In POW 1 s sChool, about 60% of the students were Catholics,.

(Note: PO\~ is highly intelligent, well educated, and very shrewd. If he is treated properly, additional valuable ini'ormation can probably be ob­ tained from him),

NOTE: IN EVALUATING INFO R.tii.t.TION CU!'-lTAINED HEREIN, CON&IDERATION MUST BE GIVEN TO THE FAC T TrL..T IT vvAS DERIVED FRON! A PRISONER OF v;AR.

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Color Control Patches Cyan Green Yellow Red Magenta White ------CONFIDENTIAL 14TH :mDEPENDENT 110RT.Lili Bi. TT.i>.LION n (j) 0 .... (!) Battalion . -(") 0 /\"' 660 Officers a I """" 1 Enlisted Men ~n cn '-- - - · -~---___! CDO :::0 16 Mortars ~ ::l ~ ( I r+ I Q.."""" ..., ------1 I -- I -- .l af-o I =r::u 1st Compu.ey 2nd Conpany il.!!!nunition Train ; Hoc.dqunrtcrs irt (280) (280) {50) (50) 8 Horturs 8 Morturs :T (j) ('I) ~------(J) :::r :::;:;ro -______T_ __ __·-- --~- j i ~ r I j f i OJ l Co:omand 1 .Gun Unit 1.1\J:l. Train i c I 1 i Corrmund ! Intend- , J:odic~l OrC.nunce I X 1Plat. ( 15~ ' (185) i i I (80) --·- L ,. · ~ · · ______.._j 1 I l~ectior:_(3q ; ancc (lOY, rs) !__ (~2__; ~ '11: l l ------I ~ I ::J m !· -- ·-- ·' ,---- I__ __ S' . I : st Plut.j' 1 2nd Plu.t. . ! 1st Plut. l I 2nd plc.-t:) (40) L__(40_)_1 ~ L- . L_ _ _j ;__ ___~_j ~ ~ i ~- ~ I ' if . l!ll I -z n -~ --_}___ =1._.-- I • -I . "2 ~ '1st Sqd (10) jzd sqd .I 0 ~ (lo~ i3d Sqd (10) I 14th ·Sqd (lO)j fl~t Squad i2nd Squad I ')-> ~ 1 Hortur 1 i 1 Mortar 1 l3r_d_Squad 14th Squud t;j ! [1 Eorta::J i l :Mortar 1 LI ___.! j ~ ~ ' NOTE: Corresponding squads of urnmunition platoons and gun platoons work habitually in direct cooperation. ------COUFIDEHTIJ1.L ~ CONFIDENTIAL - f GRAM "All -...._./

(80 kg)

_eo rom

Powder Train to Booster Charge

{110 kg)

Total Length o~ Projectile \ 1.7- 1.8 meters. Length of Tube 1.20 meters Weight of Projectile 272 kg (Approx)

11 - 12 Bowder Bags

Booster Charge

Electrical Ignition P~wder Train

Hollow Space {T.(L'.Lighten Tube for Carrying)

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D:EAGRAM B

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Scale

Bolts slide in slots in base, permitting slight changes in deflection & range.

Top View of Base Plate

Base Backed By Dirt (45° Angle) Cross Section Base of Logs (45° Angle) Cross Section ------C 0 N F I D E N T I A L

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