Reports from the central African country suggest a Christian militia group have beheaded a Muslim teenager, leading to counter-attacks from Muslims.
The country suffers from instability caused by religious differences and violence broke out in 2014 after Christian gangs called the anti-balaka drove Muslims from their homes in the south.
"Two young Muslims leaving the city were detained by anti-balakas who beheaded one and wounded another.
"We went to take the body back to the mosque," said Captain Ahmat Nejad, a spokesman for the mainly Muslim Seleka faction in Reuters.
"This triggered the anger of young Muslims who have carried out reprisals against Christians."
Father Félicien Endjimoyo of the Diocese of Bambari, where the killings took place, said as many as 16 people have been killed.
Violence broke out in March 2013 when Seleka rebels seized power.
The Christian anti-balaka group have been accused of carrying out attacks killing thousands.
It is thought around a million people have been displaced by the fighting so far.
