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Hong Kong (CNN) — Hong Kong police fired water cannons and tear gas at protesters in the streets surrounding a central university Sunday, hours after a police officer was shot with an arrow during a siege of the fortified campus.
In a new escalation after nearly six months of demonstrations in the fiercely divided city, police warned via Facebook that if protesters continued to use petrol bombs and bow and arrows, they would respond by using minimum force and, given no other choice, live rounds.
Earlier in the evening, police had told protesters to leave the area and stop all illegal assemblies as they were "planning for the next round of operation."
Hundreds of protesters with bricks, petrol bombs and makeshift barricades had held off riot police on roads surrounding the campus in the city's Hung Hom district, just across Victoria Harbor from Hong Kong Island, for hours.
Unlike other campuses, such as the Chinese University of Hong Kong, the Polytechnic University sits in the center of the city, close to a number of major roads including a cross harbor tunnel.