Protests in the streets of the Indonesian capital, Jakarta, turned violent on Tuesday night, with police reportedly using tear gas and water cannons to disperse demonstrators who had set fire to vehicles and a police dormitory.

Anies Baswedan, the governor of Jakarta, was quoted by local media as saying that six people had been killed and 200 injured in the unrest. There has not yet been official confirmation from police.

Read more: Joko Widodo declared winner of Indonesia's presidential election

President Joko Widodo said on Wednesday that authorities have the volatile situation under control. Flanked by the military chief and other top leaders, Widodo said: "I will work together with anyone to advance this country, but I will not tolerate anyone who disrupts the security, democratic processes and unity of our beloved nation."

"These protests do not come out of the blue," Felix Heiduk, an Indonesia expert at the German Institute for International and Security Affairs (SWP) told DW. "They have to be understood in the context of growing polarization in Indonesian society over the past five years," he added.

Social media curbs 

The protests began Tuesday afternoon, when thousands of supporters of Prabowo Subianto gathered outside the headquarters of the Indonesian election commission in Jakarta after official election results were released confirming the victory of Subianto's rival, Widodo.

Indonesian National Police spokesman Dedi Prasetyo said clashes with police began Tuesday night and continued through into Wednesday morning, adding that at least 20 people had been arrested.

Images broadcast on Indonesian television and social media showed demonstrators throwing flaming objects at riot police as smoke filled the air. As of mid-morning on Wednesday, live broadcasts showed demonstrators still on the streets of Jakarta. 

Read more: Indonesia elections: Personality, religion and politics

Indonesian police said they had deployed more than 30,000 police across Jakarta in anticipation of violent protests. The country's security minister said the government will also restrict access to social media to prevent the spread of fake news. "To avoid provocations, the spread of fake news through the community, we will limit access to certain features on social media," said Wiranto, who goes by one name.

Refusal to concede defeat

The initial protest reportedly ended peacefully, but tensions between police and demonstrators escalated after demonstrators refused to leave the area around the election headquarters and began throwing objects at security forces.

Prabowo Subianto's supporters accuse President Widodo's campaign of electoral fraud. Subianto has refused to accept the election results, and has declared himself the winner of presidential election that was held on April 17.

"The inconsistency is reflected in the ambiguous step between encouraging people to take to the streets and denying that the rioters were not Prabowo's supporters," Arif Susanto, a political expert at Exposit Strategic in Jakarta, told DW. "It's also evident in Prabowo not trusting the constitutional court but wanting to contest the election results in the court," he added. "This is the political expression of anxiety in his elite circle." 

According to the Indonesian Election Commission, Widodo won the election by a margin of about 10%. Prabowo's campaign has said they will challenge the election results in Indonesia's constitutional court, although they have provided no evidence to back up their claims.  

sri, wmr/se (AP, AFP, Reuters, dpa)

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