Thousands of mostly young people have rallied for the third consecutive day in Serbia, protesting against Prime Minister Aleksandar Vucic being elected the country's next president

Crowds on Wednesday marched through the capital Belgrade and other cities, blowing whistles and chanting slogans such as "Vucic, you stole the election" and "End the dictatorship". 

Vucic, who will take office as president in late May, won Sunday's presidential election with a clear majority, garnering 55 percent of votes in the first round.

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The protesters have gathered on the streets in response to calls on social media. It was not clear who is organising the events, although government officials says the demonstrations are the work of political opponents.

Protesters said they see Vucic as an autocrat and his Serbian Progressive Party as corrupt and instrumental in what they say was a fraudulent election.

Demands posted online by one group of students included dismissing the election commission, the media regulator and top editors of the state RTS TV for allegedly failing to facilitate a free and fair vote.

"I am here because I think that there is no democracy in this country any longer," Belgrade protester Mihajlo Saranovic told the Associated Press news agency.

"I think that something needs to change and I am here to express my discontent with the current situation," he said.

The students said they will demand early parliamentary elections if their requests are not met.

Protesters hold an image of newly elected President of Serbia Aleksandar Vucic with a tag line reading 'It's over' [EPA]

Nebojsa Stefanovic, Vucic's interior minister, said on Wednesday that the street protests were "highly political" and orchestrated by the opposition candidates who lost the election.

On Monday, Vucic said that "everyone has a right to be unhappy with the election results."

"It is fine as long as it is peaceful," Vucic said.

The opposition has alleged the election was marred by major irregularities, including muzzling of the media, voter intimidation and bribes.

Source: News agencies