A Koh Kong police lieutenant colonel, wanted in connection with Cambodia's

largest drug seizure, is believed to have fled to Vietnam.

An arrest

warrant has been issued for Lt Col Lim Ly, the deputy chief of Koh Kong's

traffic police, while two of his subordinates and three other men are being

detained in the Capital's T3 prison.

The six are accused of trying to

smuggle 71kg of opium alkaloid, which police said was a partially processed form

of heroin.

Brigadier General Heng Peo, chief of the Phnom Penh anti-drug

police, said the haul was found on a boat in the Koh Kong port of Sre Ambel Aug

11.

The drug had an estimated United States street value of around $15

million, he said.

The five men arrested were identified as: police Major

Un Sroas, 31; police Captain Yim Soksimara, 32; Yi Peo, 18; Chhuong Son, 36; and

Chhan Fai, 27.

Gen Peo said Major Sroas had told police that he and

Captain Soksimara were ordered to guard the boat in Sre Ambel by Lt Col Ly, but

did not know that drugs were on board.

Ly, whom Gen Peo described as the

smugglers' ringleader, had since escaped to Vietnam. If caught, he and the other

five men faced 15 years in prison if convicted.

Gen Peo said the opium

was believed to have come from somewhere in the Golden Triangle and bound for

Hong Kong or Vietnam.

He said it was Cambodia's biggest ever drug bust.

It followed an increased anti-drug effort by police this year, with 12 arrests

being made so far.