Taipei, Sept. 22 (CNA) The Coast Guard Administration (CGA) said Monday it detained four Chinese nationals and seized their vessel in a drug bust earlier this month that uncovered more than 700 kilograms of narcotics. The vessel had switched off its automatic identification system, the CGA said. Officers found 48 bags of narcotics in a hidden compartment, including 10 bags of heroin weighing 209.3 kg, 36 bags of cannabis weighing 472.39 kg, one bag of methamphetamine weighing 18.2 kg and one bag of nimetazepam weighing 18.3 kg, according to the CGA. The captain and three crew members, all Chinese nationals, have been detained on suspicion of violating the Narcotics Hazard Prevention Act. They are being held incommunicado as the Tainan District Prosecutors Office investigates, Hsu said.