Military police in Preah Sihanouk province on Sunday briefly detained nine Chinese nationals and sent four others to court after they were rounded up at a karaoke parlour while consuming drugs.

National Military Police spokesperson Eng Hy said Tuesday that Shi Xue Cheng, 41, Pan Yi, 29, Li Xin, 29, and Chen Xiao Tian, 39, were arrested on Sunday night together with nine other Chinese nationals who were later released after the authorities found that they were not involved in any illegal activities.

Hy said police seized nearly 3kg of suspicious substances, believed to be drugs, at a nightclub in Sihanoukville.

Prosecutor Kieng Suntharo said one of the four was charged with facilitating drug use, which carries a prison sentence of up to five years.