On January 21, 1969, Company B was assigned to sweep and clear Highway 7A from north of Trung Lap to the junction of Highway 1. At 0745 hours, the sweep was delayed until the fog lifted. The sweep was resumed and at 0806 hours, a 30 pound AT mine was located and destroyed. At 0837 hours, Company B reported that while moving through Trung Lap one vehicle hit and killed a pig. At 0939 hours, an APC from Company B detonated an AT mine on Highway 7A, one kilometer north of Highway 1 at XT 572178. The blast flipped the track over pinning one Bobcat underneath, killing him. Another Bobcat was wounded.