COLOMBO (AFP) -- Sri Lankan authorities Saturday freed nearly 2,000 convicts to mark the island's 58th anniversary of independence from Britain, a prison spokesman said.

A presidential pardon helped 1,995 inmates, including 57 women, serving time for minor offences to leave prisons across the island, the spokesman said.

The convicts were freed to coincide with celebrations here at Colombo's Independence Square public park.

"We arranged to release just over 2,000 convicts, but the paper work was completed only in respect of 1,995 and they are being released from prisons across the island today," the spokesman said.

"The amnesty did not apply to those convicted of contempt of court and serious crime."

Meanwhile, dozens of opposition activists kept up a sit down protest here demanding the release of opposition legislator S. B. Dissanayake who was jailed in December 2004 for two years on a charge of contempt of the Supreme court.

The independence amnesty did not apply to Dissanayake, prison officials said.