Thanh Hoa police announced the probe and detainment of the suspects for four months based on the accusation they facilitated illegal use of narcotic substances Thursday.

Hoang Van Dong, 37, was identified as the kingpin; his accomplices being 34-year-old former traffic lieutenant Nguyen Tat Thang and five others.

On May 21, police raided a villa in Sam Son Town and found 16 people under the influence of drugs. Thang and 13 others subsequently tested positive for heroin.

Dong said on May 20, he bought eight ecstasy pills and invited his friends to the villa to bid him farewell before embarking on a sentence for a crime he committed prior to the party.

Each year around 1,600 people die of drug overdoses in Vietnam. Around $93.7 million is spent on buying drugs and $44.6 million on running rehab facilities.