BANGUI (Reuters) - More than 40 people were killed and dozens wounded in Central African Republic in an attack on a Catholic mission sheltering 20,000 refugees, a regional lawmaker said.

The attack happened on Thursday in Alindao, a town 300 km (200 miles) east of the capital Bangui. Thousands of people were forced to flee when the mission was set on fire, the United Nations said.

“We have counted 42 bodies so far, but we are still searching for others. The camp has been burnt to the ground and people fled into the bush and to other IDP (internally displaced person) camps in the city,” Alindao lawmaker Etienne Godenaha told Reuters.

A humanitarian source confirmed that more than 40 people were killed.

U.N. humanitarian coordinator in Central African Republic Najat Rochdi said in a statement: “This vicious cycle of repeated attacks against civilians is unacceptable.”

Thousands have died and a fifth of Central African Republic’s 4.5 million population have fled their homes in a conflict that broke out after mainly Muslim Seleka rebels ousted President Francois Bozize in 2013, provoking a backlash from Christian anti-balaka militias.

Depite electing a new leader in 2016, the country has continued to face political instability and tit-for-tat inter-communal violence.