Fears were raised on Monday that the latest outbreak of violence in the capital of Madagascar could derail a new round of peace talks due to start this week in Senegal.
Four soldiers loyal to Madagascar's former president Didier Ratsiraka were reportedly killed in a gun battle as supporters of Marc Ravalomanana raided the former prime minister's residence, the only government office still under the control of Ratsiraka in Antananarivo.
French news agency AFP reported that newly appointed Prime Minister Jacques Sylla placed his predecessor, Tantely Andrianarivo, under house arrest. But Andrianarivo was released after several hours.
The move by Ravalomanana's supporters was seen as the final step in consolidating Ravalomanana's government in the Indian Ocean Island. However, one analyst told IRIN that the siege of the government ministry "only complicated a very sensitive situation".
"It has become an elaborate game between Ratsiraka and Ravalomanana. On the one hand they decide to restart negotiation while threatening each other with violence and in the process a bridge is blown up and ministries are taken by force. It says a lot about their committment to peace on the island," Madeleine Ramaholimihaso, who headed the consortium of civil society organisations that supervised the December presidential poll, told IRIN.
Ravalomanana's defence ministry last week warned it would send troops to clear Ratsiraka's crippling blockade of the capital if it was not dismantled by Monday. And hardliners on Ratsiraka's side have threatened to use force to evict Ravalomanana's supporters from the northeastern port city of Tamatave if they do not leave by next week.
Both men announced on Friday that they will renew reconciliation talks in Dakar starting on 29 May. At an earlier round of talks held in April, the two rivals agreed to a recount of the December vote as the first step towards ending their row.
But Ratsiraka rejected the result of the recount, which gave his election rival an absolute majority in the vote and therefore the presidency. A second meeting planned for 13-14 May never materialised and Madagascar is now rife with threats of military aggression from both camps.
L'Express daily newspaper said that negotiations were likley to focus on forming a government of national unity.
Sporadic violence has claimed about 40 lives since the crisis began.