Subianto lost the Indonesian presidential election to Widodo for the second time, after facing each other in 2014.
Indonesia held its general election on 17 April, during which, for the first time in the history of the country, people simultaneously elected the president, the vice president and members of the national parliament and local legislative bodies.
Earlier, Prabowo's supporters had reportedly pledged to protest peacefully if the official result confirmed Widodo's victory.
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The head of the Indonesian National Police, Tito Karnavian, said in a statement on Thursday that police and security forces would prioritize ensuring security and stability in the country in the period after the general election, until the announcement of the final results on 22 May.
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