JAKARTA, Indonesia (AP) — A day after Indonesia’s presidential elections failed to produce a clear winner, Jakarta’s police chief promised to prevent violence by cracking down on anyone celebrating prematurely. With both candidates continuing to claim victory, the next leader of the world’s third-largest democracy could be decided in court.

Wednesday’s third direct presidential vote went smoothly, but fears of unrest surfaced after Jakarta Gov Joko Widodo and ex-army general Prabowo Subianto both declared a win after the quick count results were released.

The apparent deadlock has raised fears of political instability in the world’s most populous Muslim nation and Southeast Asia’s biggest economy. It could not only stymie the economic development but also stall the nation’s young democracy, which has just begun to flourish after decades of authoritarian rule.

Widodo, known as Jokowi, came out ahead with 52 per cent of the vote, according to the three most credible unofficial quick counts. But Subianto pointed to lesser-known surveys showing he came out on top, but later said he would consider the election commission’s announcement in two weeks as the “only formal result of the election”.

Both candidates met separately in private meetings with outgoing President Susilo Bambang Yudhoyono on Wednesday night. Widodo emerged afterward to urge supporters, who were setting off fireworks, waving flags and riding motorbikes around the heart of the capital, to stand down.

“We appeal to the party’s members and sympathizers, volunteers and supporters, you don’t need to parade to celebrate the presidential election victory. It’s better for us to pray and give thanks,” he said. “We need to minimise friction that could arise.”

Yudhoyono also urged both sides to “restrain themselves” and not allow their supporters to publicly declare victory.

“We will not hesitate to take firm action,” said Jakarta police chief Maj Gen Dwi Priyatno. He added that security forces were working closely with both camps “to anticipate everything that could cause friction among people and lead to massive rash acts”.

The election commission, which began tallying the votes, will produce the official results by July 22. But if either candidate refutes the outcome due to evidence of fraud or other voting irregularities, the case will go to the Constitutional Court. The judges have two weeks to make a ruling after receiving complaints.

Subianto, who has ties to the country’s political and business elite and was once married to former dictator Suharto’s daughter, has already raised concerns about the quick count’s legitimacy. The tally is a representative sample of votes cast around the country and civil society organisations have used the method to accurately forecast the results of previous elections.

“Prabowo-Hatta is leading the real vote count in many regions,” Subianto said, referring to his running mate Hatta Rajasa. “That is the situation.”

Some analysts say that in a country plagued by corruption, there is plenty of room for bribery, intimidation or other tactics to sully the official count of more than 140 million ballots that must be transported to regional centres, often from remote areas scattered across Indonesia’s archipelago — spanning roughly the width of the United States.

“The Jokowi camp is clearly worried that there will be fraud in the aggregation process,” said Jakarta-based political analyst Paul Rowland. “There are plenty of opportunities there to change the numbers.”

Confidence in the Constitutional Court has also recently been shaken, though some are already predicting that’s where Indonesia’s next president will be decided. Last month, its former chief justice was jailed for life for accepting bribes while ruling on a regional election dispute.

“Considering victory claims from both candidates, it seems difficult to avoid a legal battle at the Constitutional Court,” said Denny Indrayana, deputy minister of Law and Human Rights. “The credibility of the Constitutional Court as the last decider of the presidential election’s results is at stake.”

But if it does go that far, others say they believe Subianto would accept the final ruling.

The election has energized the country of 240 million. Turnout was estimated around 75 per cent in a race that was polarised by two very different figures.

Widodo, 53, of the Indonesian Democratic Party of Struggle, is the first candidate in a direct presidential election with no ties to former late dictator Suharto, who ruled for 30 years before being overthrown in 1998. He is a former furniture exporter from humble beginnings who has built a reputation of being an efficient leader, getting elected to run the capital in 2012. He is seen as a man of the people and ran a more grass-roots campaign.

Subianto, 62, of the Great Indonesia Movement Party, comes from a wealthy, well-known family and is accused of widespread human rights abuses, including ordering pro-democracy activists kidnapped before Suharto’s fall. He surged forward in the polls just weeks before the election after picking up endorsements from most of the country’s major political parties and running a more well-oiled campaign. He appealed to many voters by vowing strong leadership that many believe has been absent with Yudhoyono, who was constitutionally barred from running after serving two five-year terms.