Serbian police used teargas and crowd control vehicles in Belgrade on Friday evening to disperse anti-government protesters who threw firecrackers and flares at officers, marking a sharp escalation in the nine-month-long demonstrations.

Protesters gathered at around 8 p.m. local time in front of the army headquarters building that was bombed by NATO in 1999. Hours later, they began throwing flares at police. Trash containers were overturned and set on fire, and one tree caught fire. Police deployed teargas to push the crowd back.

Demonstrations also took place in Novi Sad, Nis, Kragujevac and Valjevo. Teargas was used in Nis. No official figures were released on the number of injured.

The protests began after 16 people died when a roof collapsed at a renovated railway station in Novi Sad. The gatherings had been largely peaceful until Wednesday when clashes left 27 police officers and about 80 civilians injured. Forty-seven people were detained.

President Aleksandar Vucic said on Friday that 3,000 police are deployed each evening across Serbia and that they are facing assaults and injuries.

Protesters have accused the government of corruption over the Novi Sad disaster and are calling for early elections. Opposition groups, students and anti-corruption watchdogs allege links between Vucic and organised crime, the use of violence against rivals, and media suppression. The president and his allies deny the allegations.

Council of Europe Human Rights Commissioner Michael O'Flaherty said he was closely following events in Serbia and voiced concern over human rights issues. He condemned what he described as disproportionate police force in Valjevo and urged authorities to avoid excessive force, end arbitrary arrests and de-escalate the situation.

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