One of the latest antitank methods now advocated by the Japanese is the use of remote-control land mines operated by engineer troops. These are men who have been trained to function as an integral part of infantry antitank assault teams. Known to the enemy as Close Quarter Combat Units, these teams have been in a state of continual development in the Japanese Army since the advent of tank warfare in the Pacific.

Instructions issued last summer to Japanese troops in the Southwest Pacific clarified the duties of these units, and outlined controlled-mine tactics, in an apparent effort to raise tank fighters to a status above that of arbitrarily organized suicide squads.

The basic components of a Close Quarter Combat Unit are its so-called "land-mine squads" and "destruction squads." These squads, of which there may be several in the unit, may be supported in action by a "reserve squad" and a "covering squad."

The successful tactical employment of such a unit seems to hinge upon the part played by the land-mine squads. These squads are composed of ten men each, with a noncommissioned officer in command of each squad. Since they must be experienced in minelaying, a good portion of the engineer strength of a unit is likely to be included in its land-mine squads. One man in each squad is designated as an "igniter"; presumably his is the responsibility of exploding the controlled mines at the proper moment. Actually, a squad must play a dual role: it not only lays and explodes the land mines, but must engage hostile supporting infantry as the antitank assault develops. Consequently, each squad is equipped with two, and sometimes three, light machine guns.

In preparing to attack hostile tanks, the land-mine squads plant remote-control mines along a road, defile, or similar corridor through which the advance of tanks is anticipated. These mines, usually electrically detonated, may be standard Japanese antitank mines, prepared dynamite charges, or aircraft bombs wired for detonation from a safe distance. It is interesting to note that the Japanese have conducted large-scale experiments with bombs used in this manner and claim that they are highly successful. When the mines have been laid, the Close Quarter Combat Unit takes an ambush position in such a way that the destruction squads can attack the tanks and the land-mine squads can engage the supporting infantry.

After the hostile tanks and infantry enter the mined area, the designated igniters explode the mines at a time when they will have the greatest effect, and the mine squads engage the infantry, attempting to separate them from the tanks.

In the resulting confusion, and while the supporting infantry is supposedly engaged, the destruction squads will rush the tanks with armor-piercing mines and prepared explosive charges, to destroy tanks not disabled by the controlled mines. Throughout this action the reserve squad and the covering squad give support fire to both the mine and destruction squads. As the action progresses, personnel of the reserve squad are used as replacements for the mine and destruction squads as they are needed.

When the tank-destroying mission has been completed, the unit withdraws under the protective fire of the covering squad.