Burmese troops on rooftops opened fire in central Rangoon on Saturday at demonstrators demanding a return to democracy and wounded at least three people, a witness said.

The witness, an engineer who was at the scene, said the troops guarding the four-story Trade Ministry building, two blocks from the famous Strand Hotel, opened fire as about 100,000 demonstrators shouting anti-government slogans marched down Strand road.The engineer said in a telephone interview that he heard about 10 shots.

Saturday's violence was the first reported since troops were ordered back to their barracks in mid-August after five days of protests that left an estimated 3,000 people dead.

The engineer said people ran for cover when the troops opened fire from above but returned after 10 minutes. Many were in an angry mood and shouts of "torch the place" could be heard, he said.

He added that the shooting was unprovoked, but this could not be independently confirmed and opposition leaders could not be contacted immediately for more details.

The violence came after a day of relatively peaceful demonstrations, led by police and Red Cross bands.

Protestors were demanding the resignation of Burma's Socialist government and the formation of an interim body until promised multi-party elections can be held.

Earlier in the day about 500 saffron-clad Buddhist monks and students began a 48-hour hunger strike in front of City Hall to press the same demands for a return to democracy.

At the same time a commercial airliner left Bangkok headed for Rangoon - the first flight to the Burmese capital for about two weeks. It carried mostly Burmese sailors stranded in Thailand by the political turmoil in their country.

Before the shooting erupted, hundreds of thousands of demonstrators marched though central Rangoon cheered on by huge crowds lining the pavements.

Last weekend the government announced multi-party elections to be held within three months, bending to opposition pressure after months of street protests and strikes that have crippled the country.

But it made no mention of stepping down in the interim.

One Burmese journalist said he did not think there was any room for compromise. "I don't think the people will be satisfied until the ruling power is ousted," he said.