Four Singaporeans and three Malaysians aged between 43 and 50 were arrested in the raid and 87.5 kilograms of ketamine was confiscated.

According to reports, officials intercepted a Malaysian tourist at Hong Kong International Airport on Saturday. The suspect was alleged to be carrying 16 kilograms of ketamine in 32 milk powder cans.

Officials then raided hotels in Tsim Sha Tsui and Hung Hom where they found more ketamine which is used as an anesthetic on animals and humans, but is widely sold illegally as a party drug.

Customs and Excise Department assistant commissioner Chow Kwong said they believed the drug was ordered for sale during the Easter holidays and some was destined for the mainland.

``These syndicates usually smuggle drugs to Hong Kong for local use, or to transfer them to other places,'' Chow said.

``We need to constantly improve our ability to smash their operations and that is why we need to cooperate with the police, the mainland authorities and with overseas countries,'' he said.

Commissioner of Customs and Excise Timothy Tong said the the department shared intelligence with mainland and overseas authorities to make the raid - codenamed ``Bayonet'' - successful.

``Police and customs have put a lot of effort into tackling the drug problem, and there has been some progress,'' he said.

``However, we cannot stop transnational syndicates trying to smuggle drugs through Hong Kong so international cooperation is necessary,'' he said.

However, Chow said, there is no evidence to suggest that Hong Kong has become a drug smuggling centre.

Meanwhile, a 34-year-old man and a 47-year-old man were sentenced to 10 and 15 years' imprisonment respectively after being convicted of manufacturing dangerous drugs. The 34-year-old man was given a reduced sentence because he pleaded guilty.

The High Court heard that officers of the Narcotics Bureau had seized more than 23,000 Ecstasy pills and 97 kilograms of raw substances and materials used in the production of Ecstasy during a raid on a Hung Hom building in 2003.

Officers arrested four men in their 30s and 40s in the raid, three of whom were eventually charged with manufacturing dangerous drugs.

One of the three, aged 31, was acquitted after court proceedings last week.

teddy.ng@singtaonewscorp.com