Iran’s government this morning declared Mahmoud Ahmadinejad the definitive winner of yesterday’s hotly contested presidential election, sparking wide protests and charges the government had suppressed votes and manipulated the results.

As late as last night, the race was considered too close to call. A top election official predicted turnout could surpass the nearly 80 percent in the election 12 years ago that brought President Mohammad Khatami to power and began the reform movement, the Associated Press reported. A strong turnout was expected to boost challenger Mir Hossein Mousavi. He was expected to do especially well among voters under 30, who account for about a third of Iran’s 46.2 million eligible voters.

Even before the vote was over, AP reported, Khatami predicted Mousavi would emerge the winner. ‘All indications suggest that Mousavi has won,’ Khatami told reporters.

Mousavi himself told a news conference late Friday night, “I am the absolute winner of the election by a very large margin,” according to The New York Times. “It is our duty to defend people’s votes,” he said. “There is no turning back.”

Today, Iran’s Interior Ministry said Ahmadinejad had won 62.6 percent of the vote, with Mousavi getting 33.7 percent, with a record 85 percent turnout. Under Iran’s election rules, a candidate has to win more than 50 percent of the vote to avoid a runoff with the next highest vote getter. With the surging support for Mousavi during the campaign, a runoff had been widely expected, if not an outright Mousavi victory.

In a statement on his web site, Mousavi said the announced results reflected the “governance of lie and dictatorship.’ He warned that ‘people won’t respect those who take power through fraud.’

Reuters and other news agencies reported that police using batons dispersed thousands of supporters of Mousavi in Tehran who held a sit-in to protest the announcement of Ahmadinejad as the winner.

A Reuters eyewitness said police were chasing and arresting some of the demonstrators.

“Police attacked people with batons and at least three people were injured,” said the witness.

“We are Iranians too,” and “Mousavi is our president,” the demonstrators chanted.

Up to 2,000 Mousavi supporters who staged a sit-in in the middle of the road clapped hands and chanted: ” Mousavi take back our vote! What happened to our vote?” They also chanted at security forces: “Police, brother, you’re one of us.”