Hospitals were conducting post-mortems to determine the cause of the deaths, he said.
Post-election protests took place in a peaceful and orderly manner at first, but they then turned violent on May 21, forcing the police to shoot tear gas to disperse the groups who supported the defeated presidential candidate Prabowo Subianto.
Some 20 protesters were arrested by the police during the clashes.
Protesters burned down a police housing facility and several vehicles in KS Tubun Street in central Jakarta in the morning.
The Indonesian Government has mobilised some 40,000 policemen and military staff to maintain security in Jakarta.
Earlier, the General Election Commission officially announced Joko Widodo was re-elected for the second term after he won 55.5 percent of votes, compared to the 44.5 percent for his rival, former general Subianto.
However, Subianto and his running mate Sandiaga Uno said that they would not accept the result and planned to take their dispute to the Constitutional Court.
The Indonesian election was held on April 17 to select the president, vice president, and more than 20,000 local and national lawmakers. The presidential race pit incumbent President Joko Widodo against retired general Subianto.
