Lone Sentry: Intelligence Notes, Japan (U.S. WWII Intelligence Bulletin, March 1944)

1. INTRODUCTION

This section contains information, from Japanese sources, about enemy counterintelligence measures and about enemy methods of handling intelligence. The counterintelligence measures were prepared for a Japanese antiaircraft unit.

2. REGARDING COUNTERINTELLIGENCE

The purpose of the counterintelligence measures outlined by this particular source was "to facilitate our [Japanese] Army's operations by exposing and eradicating Fifth Columnists in the vicinity of antiaircraft-unit positions."

The Japanese issued the following instructions:

a. Select an officer to take charge of counterintelligence (he may be the unit adjutant or its chief intelligence officer).

b. Strictly supervise officers' and men's speech and behavior, especially their personal communications.

c. Strictly abide by regulations concerning private correspondence, and see to it that there are no leaks.

d. Work for thorough moral training in counterintelligence.

e. Keep a vigilant watch for fifth-columnist activities, such as raids and infiltrations.

f. Try to secure information from natives about enemy infiltrations by submarine, by parachute, or by air-landing.

g. Keep a strict watch over the activities of neutral foreigners and of Axis nationals in particular.

h. Give guidance to the natives, mainly in order to keep them friendly. Guard against activities of native enemy sympathizers.

i. Watch for even the slightest change in conditions in areas where the enemy drops propaganda leaflets. Keep rumors strictly under control.

j. Properly safeguard (or burn) classified military documents. Be especially careful in handling maps or sketches on which troop dispositions are indicated.

k. Take precautions as to the types of documents carried by aircraft crews, patrols, liaison men, and so forth.

l. Limit printed matter to the minimum number of copies required.

m. Make certain that misprints, original stencil sheets, and waste paper are burned.

n. Report any type of disorder to headquarters, and notify the nearest MP.

3. REGARDING INTELLIGENCE

a. Reliability

The Japanese, according to an enemy source, rate the reliability of intelligence as follows:

A—undoubtedly reliable;
B—probably reliable;
C—for reference, although authenticity is undetermined.

b. Collection

In their "plans for collecting intelligence," the Japanese require that the following points be covered:

(1) Data for estimating hostile offensive plans;

(2) Shifts in aircraft units and their movements;

(3) The state of newly established airfields and their equipment;

(4) The situation with regard to warships and the movement of supply transport forces;

(5) The state of signaling and broadcasting;

(6) Hostile unit numbers;

(7) The state of airborne raiding forces;

(8) Propaganda strategy and counterintelligence data;

(9) The attitude of the natives;

(10) Activity of hostile elements, especially the source of this activity;

(11) Men and articles dropped by parachute;

(12) Existence or nonexistence of hostile radio waves and signals;

(13) Emphasis on reconnaissance of suitable landing places for airborne raiding forces, suitable airfields, and suitable debarkation points;

(14) State of communications system; conditions conducive to local self-sufficiency;

(15) Nature of soil, resources, and land suitable for cultivation; and

(16). General terrain and weather and atmospheric data.

"Try to capture and make use of hostile natives and prisoners," this Japanese source adds.

Elsewhere certain Japanese units were told to use "enemy methods in the accumulation of intelligence, particularly with regard to taking prisoners and examining abandoned corpses."

With regard to prisoners, a Japanese Army treatise reads:

The capture and questioning of prisoners is a profitable way to collect intelligence. By direct action on our part, we can capture hostile forces with comparative ease.

Therefore, all units—especially those on the front line, as well as sentries and patrols—will take advantage of opportunities to execute surprise attacks, feint attacks, and ruses in general in an effort to take prisoners. If abrupt challenges are unavoidable, prevent the escape of opposing forces by endeavoring to wound or mortally injure them with a sudden blow. Show originality and daring in action. High ranking officers must lead the way and encourage the taking of prisoners.

With reference to searching corpses and handling captured items, a Japanese Army order says:

There are various items on enemy corpses, which are to be searched immediately after battle. The items taken from the corpses—especially documents, diaries, and maps must be collected for study.

Although, in general, all units have considered the collection of such profitable material, lower units have not yet given it their full consideration. Only abandoned weapons and provisions are being collected. Thus collection of the most valuable intelligence material is being sadly neglected. It may be necessary to detail men from a reserve unit to collect this material.

Captured matériel, except items to be used immediately by front-line units, must be sent back for study, repair, and preservation for future use.