At least 22 people, including 15 local chiefs and three local members of staff of the medical charity Medecins Sans Frontieres, have been killed in an attack on a town in the Central African Republic, officials said.

The attack on Saturday was in Nanga Boguila, about 450km north of the capital Bangui.

Gilles Xavier Nguembassa, a former member of parliament for the area, said four people were killed as the assailants approached the town but most died when an MSF-run clinic was attacked while local chiefs were holding a meeting there.

"Fifteen of the local chiefs were killed on the spot," he told Reuters news agency, citing witnesses he had spoken to.

A spokesman for MSF confirmed the deaths of its staff but gave no further details.

Nguembassa said the incident took place when mainly Muslim Seleka rebels came to the clinic in search of money.

Seleka officials were not immediately available for comment.

The Central African Republic has been torn apart by cycles of religious violence that have forced a million people from their homes.

Mass exodus 

On Sunday, heavily armed African and French peacekeepers escorted some of the last remaining Muslims out of Central African Republic's restive capital, trucking more than 1,300 people who for months had been trapped in their neighbourhood by Christian armed groups.

The latest wave of exodus further partitions the country, a process that has been underway since January, when a Muslim rebel government gave up power nearly a year after overthrowing the president of a decade.

The UN has described the forced displacement of tens of thousands of Muslims as "ethnic cleansing".

While previous groups have been taken to neighbouring Chad, Sunday's convoys were headed to two towns in the north on the Central African Republic side of the border.

The long-chaotic country's political crisis has prompted fears of genocide since it first intensified in December when Christian fighters stormed the capital in an attempt to overthrow the Muslim rebel government.

They soon began attacking Muslim civilians accused of having collaborated with the much despised rebels. 

Source: Agencies