The 22-year-old was caught during the raid in a flat - believed to be a core drug warehouse - in an industrial building on Castle Peak Road, Cheung Sha Wan, on Wednesday.

He will appear in West Kowloon magistrates' courts today on a charge of trafficking. Sources said he is a Baptist University student.

Officers seized 141 packs of the drug ice weighing 148 kilograms disguised as teabags, and 229 packs of heroin weighing 86 kilograms.

The operation was conducted to uproot a trafficking syndicate, following the arrests of 12 others, aged 16 to 45, from May to last month, for trafficking, manufacturing, conspiracy to traffick dangerous drugs and obstructing officers during raids on five drug warehouses in Hung Hom, Sheung Shui, Fan Ling, Ma On Shan and Tseung Kwan O.

Officers confiscated 96.3 kilograms of drugs in the fiveplaces, including 44.3 kilograms of heroin, 32.6 kilograms of cocaine, 13.2 kilograms of ketamine and 6.2 kilograms of ice.

The Cheung Sha Wan warehouse is believed to be a central storage facility, with the drugs taken to the five smaller places.

Superintendent Chan Kon-ming said among eight of the 13 arrested were below 21 years old, with four aged 18 or below. Six were unemployed and two are students.

He said the teenagers were used to rent and guard the warehouses and transport drugs, and were paid a few hundred to a thousand dollars.

"Syndicate members never got involved themselves. By doing so they transfer all the risks on the teenagers," an officer said.