BOGOTA (Reuters) - Fighting between Colombia’s ELN rebel group and a crime gang for control of a drug trafficking area in the eastern part of the country has displaced 850 people, including some 400 children, a local official said on Tuesday.

The residents fled rural areas in Hacari municipality, in Norte de Santander province along the border with Venezuela. Mass displacements continue to occur regularly in Colombia, despite a 2016 peace deal with the largest rebel group, the Revolutionary Armed Forces of Colombia (FARC).

The National Liberation Army (ELN) and the gang, known as Los Pelusos, have been fighting in the area since March, Hacari mayor Milciades Pinzon told local Caracol Radio, but combat intensified during the past week.

“People left Friday, fleeing from recent combat between the two groups. They didn’t find any other way to save their lives except coming to the municipal capital,” Pinzon said.

Coca - the base ingredient in cocaine - is grown in the area and the country’s porous border with Venezuela is a well-known drug smuggling corridor.

Though thousands of FARC fighters demobilized last year and the group has now become a political party, lucrative drug trafficking and illegal mining areas abandoned by the group have become the focus of fierce fighting between the ELN, crime gangs and FARC dissidents who refused to lay down arms.

In the first half of the year an average of 98 people per day were displace by fighting, the human rights ombudsmen has said.

New President Ivan Duque, who took office in August, has promised to crack down on traffickers and rebels.