Antananarivo  - A peace conference of Madagascar's political parties and civic groups that had been scheduled to start Thursday was postponed indefinitely after opposition leader Andry Rajoelina refused to participate, organizers said.

The Council of Christian Churches in Madagascar, which was tasked by the United Nations with organizing the three-day conference aimed at ending six weeks of unrest on the island, said the dialogue had been postponed "until later."

Rajoelina, who is under UN protection after leading a campaign of demonstrations to unseat President Marc Ravalomanana, made known Wednesday that he and other opposition groups would not participate in the dialogue.

Tensions have risen sharply in the world's fourth-biggest producer of vanilla in recent days, where clashes between government and opposition supporters and a new wave of looting have reportedly claimed several lives.

Local media reported Thursday that security forces had opened fire on suspected looters in the capital Antananarivo during an overnight curfew, allegedly killing five people and injuring several. No official confirmation was available.

Observers say Rajoelina, the ex-mayor of Antananarivo, who is calling for a new interim government that he proposes to lead, has been bolstered by the president's loss of control over the army.

On Wednesday, a group of mutinous soldiers ousted the army chief of staff and replaced him with their own leader. Andre Ndriarijaona, the new leader, confirmed the army was no longer taking orders from the president but said he was open to talks.

The embattled president of seven years, whom the opposition accuses of authoritarianism and economic misrule, had been talking up the peace talks as a "major event" for the country.

Representatives of the diplomatic corps, in a statement Wednesday, also described the conference as the "only and last chance" for a peaceful solution to his standoff

Western diplomats have privately expressed fears of civil conflict in the absence of timely dialogue.

This week, 18 people were injured when government and opposition supporters clashes in the street. Two local newspapers reported that two people were killed in the clashes, but that their bodies had not been taken to hospital.

The army on Tuesday gave the two leaders 72 hours to resolve their differences. Failing that, the army said it would impose a solution.

Over 100 people have been killed since the opposition began a campaign of near-daily demonstrations in the capital in late January over a clampdown on media freedoms and several controversial spending decisions by Ravalomanana, a millionaire businessman.

The security forces have fired several times on unarmed demonstrators, killing dozens.

Diplomatic sources say Rajoelina may be counting on the army calling fresh elections that he likely feels he can win.

Earlier this week he was given sanctuary in the French embassy, Madagascar's former colonial power, but he quickly left for an undisclosed location following an angry protest by the president's supporters outside the building. (dpa)