The violence – the bloodiest in recent years – last week led president Gustavo Petro to accuse the ELN of committing a war crime and suspend peace talks with the group.

The ELN has launched an offensive against former members of the Revolutionary Armed Forces of Colombia (FARC) rebels who demobilised under a 2016 peace deal, their families and some community leaders, Velasquez said from the eastern city of Cucuta.

Colombian rebel groups have historically fought the government, right-wing paramilitary organisations and each other for control of territory and illegal income sources like drug trafficking. Armed groups also often target civilians who oppose their activities.

Velasquez said 8,000 people had been displaced by fighting. Though he gave a death toll of 60, the governor’s office in Norte de Santander province and the human rights ombudsman said the toll was 80.

The ELN said in a Sunday statement the demobilised FARC rebels had returned to arms and that victims were not civilians.