A fresh wave of violence has forced 40,000 more people to flee from their homes in the Central African Republic (CAR), bringing the number of refugees in the country's east to 100,000, an NGO says.

The Norwegian Refugee Council (NRC) reported on Monday that ongoing fighting in the CAR has also left more than 100 people dead since April.

In the eastern province of Haute-Kotto, clashes between armed groups since June have forced almost the entire population of its regional capital Bria to flee for their lives.

READ MORE: CAR tops list of 'world's most neglected' crises

The humanitarian group estimates that nine in 10 of the important mining town's 47,000 population have fled their homes because of the latest violence.

"We are worried about the situation in the city, and we call the humanitarian community to support the organisations already in the area to assist us," Fatimatou Sai, a refugee, was quoted as telling the NRC.

A peace deal signed by 13 of the country’s 14 armed groups in June brought hope of peace to the war-ravaged country. But hopes faded when more than 50 people were killed in fighting that broke out the same day.

"Those 43,000 displaced persons have lived in dire conditions since the beginning of this crisis. Lack of access to health services, drinking water, and adequate shelters are some of the issues that worsened with the conflict," said NRC staff member Severin Modowanza.

People have fled to seven locations across the eastern region, including two churches and a hospital, NRC said.

The group said it was working to provide legal aid for those who have fled their homes, while extending humanitarian assistance such as food, water and shelter to the displaced people.

The country, one of the poorest in the world, has been plagued by inter-religious and inter-communal conflict since 2013 between the mainly Muslim Seleka rebels and the Christian Anti-Balaka militia that started after the overthrow of leader Francois Bozize.

In May this year, the UN's refugee agency said that there were more than 500,000 internally displaced persons in the entire country.

CAR has enjoyed little stability since gaining its independence from France in 1960.