A peace tribunal in Colombia has ordered the arrest of a former rebel commander for failing to contribute to reconciliation efforts mandated by a recent peace deal.

Hernan Velasquez was one of the most-feared commanders of the Revolutionary Armed Forces of Colombia behind some of the deadliest attacks in the country's half-century conflict. But he laid down his weapon in 2016 along with thousands of other guerrillas as part of the peace deal.

Since then he has failed to appear before the peace tribunal to confess his war crimes. As a result, magistrates on Friday said he would no longer be eligible for benefits including protection from arrest.

Last year he went underground with other prominent rebel leaders who've criticized the government for not living up to its commitments.