Hong Kong Police on Sunday arrested 17 people linked to three bomb attacks in late January at a public hospital and two checkpoints and seized 2.6 tonnes of explosive chemicals raiding several places in the city.

The arrestees – 12 males and 5 females – were responsible for bomb attacks at a public hospital and two checkpoints, said police

The seized chemicals are “commonly used by terrorists”, police said after the operation, which began late Saturday and continued till early Sunday.

The arrestees – 12 males and 5 females – are aged between 21 and 53 years, and believed to members of the same group.

The 17 are allegedly responsible for bomb attacks at a toilet of the Caritas Medical Centre on Jan 27, at the Shenzhen Bay checkpoint on Jan 28, and in a train at the Lo Wu checkpoint on Feb 2, Senior Superintendent of the Organised Crime and Triad Bureau Steve Li Kwai-wah said at a press briefing Sunday afternoon. 

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The police seized 2.6 tonnes of different kinds of chemicals from a unit of a commercial building in Tai Kok Tsui. They are all raw materials believed to be manufactured into powerful homemade explosives “commonly used by terrorists around the world”, said Senior Bomb Disposal Officer Alick Bryce Mcwhirter.

In another unit of the same building, police also seized 3 semi-finished bombs, each containing 1.5 kilograms of explosives inside. A batch of remote control devices used to trigger bombs were also found at the site. 

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They are sophisticated electronics that use radio control as a triggering system, Mcwhirter said. 

The bombs are believed to be prepared for use during public activities to attack the police, according to Li.

Police will conduct further operations regarding frequent bomb attacks and bomb hoaxes since January, he added.