Serbian Prime Minister Milos Vucevic resigned on Tuesday, becoming the highest-ranking official to step down amid a wave of anti-corruption protests that have spread across the country.

The anti-government demonstrations sprang up in the wake of the roof collapsing at a railway station in the city of Novi Sad, killing 15 people and leading to calls for Vucevic to quit.

What began as small gatherings in Novi Sad have ballooned and spread to the capital Belgrade as students, teachers and other workers have turned out in their thousands to blame the station disaster on corruption within the government of President Aleksandar Vucic.

The minister for construction, transportation and infrastructure, and the trade minister have already stepped down because of the incident, but that failed to quell the protests.

"I opted for this step in order to defuse tensions", Vucevic told a news conference on Tuesday, announcing his resignation. He said the mayor of Novi Sad would also resign. 

"With this we have met all demands of the most radical protesters."

The protests, which included students putting up a blockade at a main junction in Belgrade this week, have been largely peaceful.

But three protesters in Novi Sad were attacked on Monday and blamed members of Vucic's Serbian Progressive Party (SNS). A young woman sustained head injuries and was hospitalised.

Vucevic said an investigation is underway. He blamed foreign interference for stoking the protests, without providing evidence.

The focus for many analysts now is how much this will affect the president, whose party easily won a snap election in 2023 but who has come under increasing pressure.

Opposition parties and rights watchdogs accuse him and the SNS of bribing voters, stifling media freedom, violence against opponents, corruption and ties with organised crime. Vucic and his allies deny these allegations.

Mario Bikarski, senior Europe analyst at risk consultancy Verisk Maplecroft, did not expect Vucic to be forced out, in part because of a lack of trusted and viable political alternatives. But he expected the protests to continue.

"The government's hesitation to accede to the protestors' demands has eroded trust in state institutions and the political leadership," Bikarski said. "Serbia will likely remain a hotbed for unrest."

Vucic is also seen as a strategic player on the international stage in view of Serbia's historic ties with Russia and the West. Serbia is a candidate to join the European Union, although it must normalise relations with its neighbour and former province Kosovo.

The opposition Kreni-Promeni party has called for an interim government made up of experts sanctioned by students who have led the protests. It has urged other opposition parties not to boycott elections if they are held.

Vucic is expected to address the nation at 2000 local time (1900 GMT).