During the four months that the 1st Marine Division’s mission had been to conduct an aggressive defense of the EUSAK left flank, Marines had become familiar with a number of Chinese small unit infantry tactics. Shortly after assignment of the division to western Korea, General Twining, the ADC, had observed that the Chinese first made a diversionary frontal assault while the main force maneuvered around UNC defenders to attack from the rear. Almost invariably the Chinese employed this envelopment technique. Occasionally the enemy also used more passive measures, such as attempting to demoralize Marines in the front lines and subvert their allegiance by English language propaganda broadcasts. These attempts represented wasted effort. Not one Marine was swayed. In some cases the Chinese were imaginative in changing their tactics or improvising new ones. This tendency had been noted as early as May by a 5th Marines battalion commander, Lieutenant Colonel Nihart, after 1/5 had engaged the enemy in a limited, objective attack: ... when friendlies marked targets with WP [white phosphorus], the enemy would immediately drop rounds of WP between the target and friendly troops to conceal the target and to confuse friendly FOs [artillery forward observers]; the enemy tried very hard to take prisoners (rather than shoot a friendly, they would often attempt to knock him out with a concussion type grenade); counterattacks were made in waves of four to seven men deployed in a formation somewhat similar to the Marine Corps wedge; snipers were deployed in holes that were mutually supporting; concerted efforts were made to knock out automatic weapons; ... for close-in fighting, the enemy used PPSH [Soviet-made 7.62mm submachine gun] guns and grenades rather than bayonets; the enemy attacked behind well coordinated mortar fire; some enemy snipers were observed to have bushes tied to their backs....[161] [161] 1/5 ComdD, May 52, p. 12.