This photo taken from the official Twitter page of Hong Kong Police Force shows suspected katemine seized during an operation on Feb 3, 2021.

HONG KONG - Hong Kong police said on Friday that they have seized over 680 kg of suspected ketamine with an estimated street value of HK$437 million (US$56 million), the largest stash of ketamine seized in a single haul in the city's history.

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Police intercepted a 23-year-old man outside a private residential unit in Yuen Long on Wednesday and found about 2 kg of suspected ketamine in his backpack. Officers then escorted the man back into the unit and found another 5 kg of suspected ketamine.

Police said it was believed that the drugs were shipped from a foreign country in December last year and arrived in Hong Kong in January

Police then searched a warehouse in Kwai Chung from where the man had taken the suspected ketamine and found 670 kg of suspected ketamine there.

Police said it was believed that the drugs were shipped from a foreign country in December last year and arrived in Hong Kong in January.

The suspect was arrested on suspicion of trafficking in dangerous drugs and will appear in a local court on Feb 6.

Police said there was an upward trend in seizures of ketamine in recent years. They will continue to step up law enforcement to crack down on the illegal activities.

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According to Hong Kong's Dangerous Drugs Ordinance, any person who traffics in a dangerous drug shall be liable upon conviction to a fine of HK$5 million and life imprisonment.