Customs officials have warned people buying unregistered Covid drugs that they may not be getting what they expect, as they revealed they’d broken up 33 smuggling cases since the start of the year.

Officers say smuggling of the oral drugs has been on the rise, and they’ve seized 257,000 tablets with an estimated value of HK$15 million since January, when quarantine-free travel with the mainland resumed.

Divisional Commander Lie Yan-ning, of Customs’ Syndicate Crimes Investigation Bureau, said most of the drugs did not appear to be registered in Hong Kong.

"Some of the drugs were submitted to the government laboratory for testing. Preliminary results show that one type of suspected smuggled Covid drug does not contain the ingredients it claimed," he said, adding that tests are continuing to find out what’s actually in the tablets.

Lie said he believed his officers had stopped most unregistered drugs from reaching Hong Kong.

He warned that unregistered drugs may not work and could be harmful. He said registered drugs would carry a five-digit registration number starting with “HK”.

Some 20 people have been arrested on suspicion of importing drugs without a licence or possessing unregistered poisons. Officers say more arrests are possible as investigations continue.