Updated

Egypt's prosecutor general ordered Monday an investigation into allegations of irregularities and forgery in the presidential election, after the candidate who narrowly lost filed a complaint and said he remained in politics despite facing corruption charges.

Mohammed Morsi of the Muslim Brotherhood edged out Ahmed Shafiq to win Egypt's highest office in the nation's first freely contested presidential vote last summer. Shafiq left the country with his family to the United Arab Emirates soon after the results were announced, without explanation at the time. But he has since said he will continue his political career, pledging to return to Egypt soon and found a new party.

Litigation against Shafiq followed his departure, with a number of investigations and court cases accusing him of corruption during his long political career under former President Hosni Mubarak, ousted in a popular revolt last year.

Egypt has seen a rising number of legal disputes between political rivals in the days following the election, as the nation struggles with an increasingly polarized political atmosphere. Shafiq had always denied the corruption charges, saying they are politically motivated by his rivals.

His call for an investigation of the election results came a day after authorities froze his and his family's assets as part of a probe into his wealth — the latest legal move against him.

After the decision, he told Egyptian media from abroad that he will have a "fierce" response to allegations that aim to "smear" his reputation. He again denied the corruption charges and said he will contest the election results, calling the alleged rigging "a crime."

"For sure there was rigging (in the elections)," Shafiq told a private TV station late Sunday. "I had information that I was a winner. But by God's will and people's will, the decision turned out this way ... I had no doubt there was forgery during the election process."

Shafiq has previously complained that some ballots were forged, that invisible ink was used during voting, and that some Christians were prevented from casting ballots. He said the incidents favored Morsi.

In Sunday's interview with private broadcaster Al-Youm, Shafiq said he has evidence of rigging and vote buying by Morsi, claiming that previous investigations into the allegations had been unfairly stopped. In another interview, he said he was not an "easy" rival. "I am continuing my political career in spite of anyone," he said.

It was unclear what the probe ordered Monday could lead to, or whether the country's top job can now be challenged because of a criminal investigation. The president's office had no immediate comment on the new investigation.

The presidential election commission, whose decisions are unchallengeable, had earlier dismissed the same complaints from Shafiq after investigating them.

A member of the presidential election committee, judge Hatem Bagato, told the website of state-run Al-Ahram newspaper that an investigation into a criminal case is different from his panel's investigation.

"We will wait for the investigation by the general prosecution to take necessary measures. The committee has no relation with the case right now," Bagato said when asked if the president's job is now in jeopardy.

In a separate legal dispute, a flamboyant TV presenter, Tawfiq Okasha, who was cleared from earlier charges of insulting President Morsi and inciting violence against him, was slapped with a four-month sentence and a fine on similar charges.

Okasha will likely appeal the decision. The lawyer who filed the case, Ayman el-Tawil, said he presented evidence to the court of live programs during which Okasha offended Morsi, questioning his victory in the elections.

In one program, nearly a month after Morsi was sworn in, Okasha said that he considers Egypt has no president, el-Tawil said, reading from the evidence he presented to the court.