BELGRADE, Serbia — At least three lawmakers were injured on Tuesday after chaos erupted in Serbia’s parliament, where 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 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 sweeling protests over a 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.