On January 16, 1974, six South Vietnamese Army officers and an American observer on the frigate "Lý Thường Kiệt" (HQ-16) were sent to the Paracels on an inspection tour. They discovered two Chinese “armored fishing trawlers” laying off Drummond Island to support a detachment of PLA troops who had occupied the island. Chinese soldiers were also observed around a bunker on nearby Duncan Island, with a landing ship moored on the beach and two additional Kronstadt-class submarine chasers in the vicinity. This was promptly reported to Saigon, and several naval vessels were sent to confront the Chinese ships in the area.