At least three lawmakers have been injured, one of them seriously, in chaotic scenes in Serbia’s parliament, during which smoke bombs and flares were thrown.

Lawmakers were scheduled to vote on a law that would increase funding for university education, but opposition parties insisted the session was illegal and should first confirm the resignation of Prime Minister Milos Vucevic and his government.

The Parliamentary chaos started about an hour after the session started on Tuesday with the opposition blowing whistles and holding up a banner reading “Serbia has risen so the regime would fall!”

Video footage from the assembly hall showed a clash first between lawmakers and later flares and smoke bombs being thrown.

Serbian media said eggs and water bottles were also thrown.

Officials later said three people were injured in the disturbance.

Parliament Speaker Ana Brnabic accused the opposition of being a “terrorist gang”.

She said one of the injured lawmakers was in a serious condition.

The incident reflects a deep political crisis in the Balkan country where months-long anti-corruption protests have rattled a populist government.

Vucevic resigned the post in January as authorities faced protests over the collapse in November of a concrete canopy in the Serbia’s north that killed 15 people and which critics blamed on rampant corruption.

Parliament must confirm the prime minister’s resignation for it to take effect.

Opposition parties have insisted that the government has no authority to pass new laws.