Five people were killed in an ambush by armed men in central Mali, the military said on Friday, blaming the attack on ethnic Tuareg separatist rebels.

The army said "elements of" the National Movement for the Liberation of Azawad (MNLA) attacked two vehicles, killing and discarding the bodies of five occupants of one vehicle before forcing passengers in the other to strip naked.

"We strongly condemn these barbaric attacks that show the true face of MNLA," armed forces spokesman Souleymane Maiga told AFP.

Other sources told AFP the death toll from the killings in the village of Gnagna on Monday was at least ten.

"The light-skinned assailants attacked civilian cars going to a fair in the Mopti region," said Bamako-based imam Hama Cisse, who comes from the area where the incident took place.

"At least ten civilians were killed and thrown into a well, and others have disappeared, with all their possessions stolen."

Pressed on what he meant by "light-skinned" the imam said he was referring to MNLA rebels "who commit crimes in Mali and then go and hide in refugee camps in Mauritania".

"There were more than ten deaths. A few survivors are on their way to Mopti," lawmaker Oulematou Ascofare told AFP.

The MNLA fought alongside Al Qaeda-linked Islamist groups against the Malian army last year, but were ousted by their former allies who occupied the north before being driven into the remote mountains by French-led troops in January.

Ibrahim Ag Assaleh, an MNLA official in the Burkina Faso capital Ouagadougou, denied any link with his movement and the attack.

"This had nothing to do with our members. We consider all these armed individuals in this area to be residual former members of terrorist groups now often used by the Malian army to create chaos," he said.