weeks earlier, but the stream could be spanned by pontoon sections. About midway between Rach Bap and the Thi Thinh crossing of Route 14, the ARVN had another small firebase. Frequent sweeps and some semi-fixed defensive positions north of Củ Chi manned by the ARVN 25th Division and Hậu Nghĩa Province RF screened the western flank of the Triangle, but PAVN resistance in the Ho Bo Woods opposite Rach Bap, and the formidable obstacle of the Saigon River, as well as a lack of resources, limited the influence that the 25th could exert on the situation within the Triangle. The ARVN was strong with infantry, armor, and mutually supporting fire bases and outposts in Bến Cát District east of the Thi Thinh boundary of the Triangle, but only one bridge, a weak span, connected the district town and the Triangle hamlet of An Dien. Battle PAVN attack On 16 May the PAVN 9th Division began their attack on with heavy artillery, rocket, and mortar concentrations falling on Rach Bap, Base 82, and An Dien. The RF company at Base 82 abandoned its bunkers, many of which had collapsed under the weight of the bombardment, late that afternoon. Rach Bap held out until about 03:00 on 17 May, its surviving defenders withdrawing in the direction of An Dien. The fighting was fierce in An Dien on the 16th, but by the night of 17 May, PAVN forces held the flattened village and its defenses. Remnants of an RF battalion, however, held the western end of the Thi Thinh bridge in a shallow blocking position, while the eastern end, by Bến Cát, was secured by ARVN forces. The PAVN dug in around An Dien but was unable to dislodge the RF positions at the bridge. Two infantry regiments of the 9th Division, with about 10 T-54 and PT-76 tanks, were employed against the dispersed 321st RF Battalion. The 2nd Regiment overran Rach Bap and continued the attack south into the Triangle along Route 14, while the 95C Regiment attacked Base 82 and An Dien. The 271st Regiment was held in reserve. Initial ARVN counterattack at An Dien The ARVN at Ben Cat were unable to counterattack the PAVN immediately at An Dien because the bridgehead held by the RF was too shallow to protect the crossing of any large forces, but III Corps commander Lt. Gen. Phạm Quốc Thuần quickly began reinforcing