[Illustration: Marine Battalion Landing Teams aboard U. S. Seventh Fleet shipping augmented III MAF forces. USS =Iwo Jima= stands off South Vietnamese coast. (USMC Photo A650016)] After this crushing defeat, the NVA shifted its emphasis from direct infantry assaults to attacks by fire. Utilizing long-range rockets and artillery pieces tucked away in caves and treelines along the DMZ, the enemy regularly shelled Marine fire support and logistical bases from Cam Lo to Cua Viet. One of the most destructive attacks was against Dong Ha where, on 3 September, 41 enemy artillery rounds hit the base and touched off a series of spectacular explosions which lasted for over four hours. Several helicopters were damaged but, more important, a fuel farm and a huge stockpile of ammunition went up in smoke. Thousands of gallons of fuel and tons of ammunition were destroyed. The enormous column of smoke from the exploding dumps rose above 12,000 feet and was visible as far south as Hue-Phu Bai.(18) The preponderance of enemy fire, however, was directed against Con Thien. That small strongpoint, never garrisoned by more than a reinforced battalion, was situated atop Hill 158, 10 miles northwest of Dong Ha and, from their small perch, the Marines had a commanding view of any activity in the area. In addition, from one to three battalions were always in the immediate vicinity and deployed so that they could outflank any major enemy force which tried to attack the strongpoint. Con Thien also anchored the western end of "the barrier," a 600-meter-wide trace which extended eastward some eight miles to Gio Linh. This strip was part of an anti-infiltration system and had been bulldozed flat to aid in visual detection.[8](19) Because of its strategic importance, Con Thien became the scene of heavy fighting. The base itself was subjected to several ground attacks, plus an almost incessant artillery bombardment which, at its peak, reached 1,233 rounds in one 24-hour period. Most of the NVA and Marine casualties, however, were sustained by maneuver elements in the surrounding area. Operation KINGFISHER, which succeeded BUFFALO, continued around Con Thien and by 31 October, when it was superseded by two new operations, had accounted for 1,117 enemy dead. Marine losses were 340 killed.[9](20)