Sri Lankan opposition leader and former army chief Sarath Fonseka has been released from prison.

Thousands gathered outside the prison to greet him as he emerged on Monday. It was not immediately clear if there were any conditions attached to his release.

President Mahinda Rajapaksa ordered the release after Sri Lanka's foreign minister met in Washington Friday with Secretary of State Hillary Clinton. They discussed the island's human rights record, amid U.S. calls for Fonseka's release.

Fonseka was serving a 30-month prison sentence for arms procurement offenses. He was also serving a three-year sentence for making allegations about the defense secretary, who is the president's brother.

Fonseka says the cases against him were politically motivated because he challenged Mr. Rajapaksa in the 2010 presidential election.

Fonseka is widely credited with helping defeat Tamil Tiger rebels after a 25-year civil war. Both he and Mr. Rajapaksa were hailed as heroes by Sri Lanka's majority Sinhalese, but they parted ways over political differences. Fonseka then quit the army and made his unsuccessful run for the presidency.