Until the final days of March, the CCF units opposite the 5th Marines had shown little aggressiveness. Regimental reports had officially cited Chinese actions as having been “extremely limited” other than their expected resistance to patrols and the Marine ITEM raid staged earlier in the month by the 1/5 two-platoon unit on Hill 31A, part of the Ungok complex. The enemy posture had, in fact, been described as one “reluctant to meet our patrols except in their positions.”[365] [365] 1/5 ComdD, Mar 53, dtd 4 Apr 53, p. 2. A regimental patrol policy early in March established as SOP a minimum of four reconnaissance and two combat patrols in each MLR battalion sector daily. Nevertheless, 3/5 had reported no contact with the enemy for the three-day period prior to the attack which was launched at 1900 on 26 March. Since the middle of the month, 1/5 had conducted nearly a dozen night combat patrols and ambushes in one- and two-squad strength to test the enemy in the Carson-Reno-Vegas area. Terminology of the operation orders read that the Marines were to make contact, capture prisoners, and deny the ground to the enemy, an injunction that--in view of events shortly to transpire--was to turn out more prophetic than anticipated. That last Thursday in March 1953 was clear, almost unseasonably warm. Just after darkness had settled down over the Korean ridges, gullies, MLR, outposts, and rice paddies, the enemy suddenly made his presence known. Up until that time it had been an average day of activity, and there had been no especially ominous overtones to the start of the night. Suddenly, at 1900, small arms and machine gun fire cracked from enemy strongholds on Hills 44, 40, 35, and 33, and tore into the left and center part of the 1/5 sector. Almost immediately, a heavy mortar and artillery preparation of 15 minutes duration exploded all along the 5th Marines MLR. A Chinese rifle platoon and half a dozen machine guns on Hill 140, about 500 yards west of Kumgok, directed additional fire on the sector. At the same time 5th Marines outposts Carson and Reno, each manned by a reinforced rifle platoon from C/1/5, came under attack from Chinese mortars and 76mm artillery. Approximately 1,200 mortar rounds struck COP Carson by 1920. As men of D/2/5, some of whom had been detailed to Carson earlier that night for an ambush, reported, “one round per second from Chinese 60mm and 82mm landed in or around [our] position during the first 20 minutes of the engagement. Thereafter, one round was received every 40 seconds until about 2200.”[366] Interdiction fires also raked Marine rear areas and supply routes. Counterbattery fire struck Marine direct support artillery positions in the 5th’s regimental sector while heavy shelling of the MLR and its battalion CPs shattered wire communication between those installations and their advance outposts. [366] 1/5 ComdD, Mar 53, p. 10.