A 77-year-old French-Spanish nun has been killed in Central African Republic, where she taught poor schoolgirls.

The diocese of Albi in southern France said in a statement that Sister Ines Nieves Sancho was found decapitated near Berberati.

The reason for the attack is unclear. Local media said it occurred in the village of Nola, in the southwest near the border with Cameroon.

Because of the heat, the diocese says, she was buried immediately instead of being repatriated to France.

Pope Francis led thousands of people in prayer on Wednesday for Nieves Sancho, saying she was "barbarously killed" in the place where she taught.

Central African Republic has seen deadly violence since 2013, often along sectarian lines. Many hoped a peace agreement in February would be a turning point.