Hong Kong bomb disposal officers were called in after an explosion in a public toilet on Tuesday night, while in a separate incident police fired tear gas and rubber bullets to disperse protesters.
The blast wrecked the toilet bowl and blackened walls after plumes of black smoke were emitted.
The incident occurred at 10.47pm in a toilet for the disabled near Lai Chi Kok public library and Mei Foo Sun Chuen, a large private housing estate.
The police’s Explosive Ordnance Disposal team was sent to the area to investigate. No one was hurt in the blast, according to the force, and no arrests were made.
It was the third incident in a week involving either explosives or a bombing.
On Sunday, two explosive devices were found at Lo Wu station, near the border with mainland China, affecting rail services for hours.
One of the devices was defused, while another caught fire and spurted white smoke. No one was hurt.
The police called the incident part of an ongoing bombing campaign and said the city was “one big step closer to terrorism” carried out by extreme, violent individuals.
Last Wednesday, petrol bombs were thrown at four police stations and a patrol car within 24 hours in a wave of action over the government’s failure to close the city’s border and supply protective gear in response to the coronavirus outbreak.
Officers were yet to determine if the three cases were related.
Separately, about 200 masked protesters and residents gathered in Tin Shui Wai in the northwestern New Territories, angry that the government has not shut down the Shenzhen Bay Port border crossing with the mainland to fight the outbreak.
Riot police arrived at a mall to disperse the crowd and at least 10 rounds of tear gas and rubber bullets were fired.
Yuen Long district councillor Ng Wai-kin said on his Facebook page that a rubber bullet had injured his back. Some reporters were also pepper sprayed.
Police made 13 arrests.
There were also protests in other areas, including Tseung Kwan O, Sha Tin and Mong Kok.
In a statement, police criticised the protesters, saying they wreaked havoc at multiple locations, including blocking Tong Tak Street in Tseung Kwan O, vandalising a shop in Sha Tin Plaza and throwing bricks outside Tin Shui Shopping Centre in Tin Shui Wai.
Their action posed a serious threat to public safety and public order, the force said.
Police warned them to stop all illegal acts or they would take enforcement action.
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