Residents of Buterere commune near the Burundian capital of Bujumbura have returned to their homes after fleeing clashes between rebel factions that left 20 fighters dead.

An uneasy calm enveloped the commune, with residents saying the fighters had left the area. The Burundian army, however, vowed to crack down on the rebels unless they abandon their current positions.

"Our defence forces did not react quickly to calls to chase the combatants away from the population's neighbourhood," the defence minister, Lt-Gen Germain Niyoyankana, said on 5 September.

Urging the residents of Buterere to alert the armed forces when there were rebels in the area, he added: "They are the ones to suffer most when security is disturbed."

The clashes, which broke out on 3 September, forced hundreds of families to flee their homes as factions of the rebel Forces nationales de libération (FNL) clashed at Mugaruro where one of the FNL wings opposed to leader Agathon Rwasa had retreated into a small forest.

The Buterere administrator, Moise Ndayisenga, said residents and local administrators had been urging the FNL factions to move out of the area, pending their assembly for demobilisation or integration.

A local resident said: "We are happy the combatants have gone."

The defence minister urged the rebel leaders and combatants not to waste time and join other Burundians in building the country. "They should come and share with others what is available and discard the thinking that they can succeed in using weapons," he told reporters. "The army will not allow the formation of rebel strongholds, and will react strongly - with arms if necessary."

He called on the army not to engage in politics. "Officers who take part in political meetings do this on their own and not on behalf of the defence forces," Niyoyankana warned.

Earlier, FNL spokesman Pasteur Habimana had accused the government of creating a faction in the FNL to force a return of combatants who remained in the Democratic Republic of Congo when the movement returned to Burundi in 2003.

The clashes were the latest sign of tensions within the FNL. Two years ago, a breakaway faction accused Rwasa of gross human-rights violations. More recently, the FNL walked out of a ceasefire monitoring team set up after it signed a truce with the government in September 2006.

The team was to start work in February but it has been delayed by the wrangles. Burundi peace mediator and South African security minister Charles Nqakula has, however, said the Joint Verification and Monitoring Mechanism would be relaunched soon so that the country's peace process could be concluded by the end of the year.