Fissures have begun to show in the ranks of Colombia’s Farc rebels after five mid-level commanders were summarily expelled from the group for refusing to demobilize and join a peace deal to end their 52-year war.

The Farc leadership said in a statement that the five commanders, who were all part of guerrilla units located in far eastern Guaviare province, were pushed out of the group for failing to follow orders.

“This decision is motivated by their recent conduct, which contradicts our political-military line,” Farc leaders said in a statement, hinting that those expelled sought to continue with the lucrative drug trade that thrives in the region.

The guerrilla group’s said its commitment to peace “cannot be blocked by a group of foolish people … who throw themselves off a cliff of personal ambition wrapping up their ignoble purpose in apparent revolutionary rhetoric”.

The statement also suggests that the five commanders have a following, and a source with direct knowledge of the situation said there could be more than 50 guerrillas under the command of the rogue rebels.

“We call on all combatants who have been tricked into this futureless path to distance themselves from this mistaken decision taken by their commanders, and to return to the ranks of the Farc where they will be welcomed by their comrades,” the statement said.

The commanders are the second group of rebels to declare their opposition to the peace deal which will see the Farc lay down its weapons and transition into a political party. In July, a First Front unit leader and some of his fighters left the group in protest against the deal.

Among those expelled is Gentil Duarte, a top Farc commander and member of the central command, who had participated in the peace talks held in Havana and was sent to Guaviare to put the First Front in order.

In the past, the Farc would have dealt with dissent with a “revolutionary trial” that could have ended with execution.

Experts calculate that about 10% of the Farc’s nearly 6,000 troops could go rogue, in line with many demobilization processes around the world. Farc rebels in some areas of Colombia where coca-growing and cocaine trafficking are strong – such as Guaviare – could be tempted to maintain control of the business, or join one of the country’s criminal gangs who are taking control of the drug routes.

Last week, the Farc in Guaviare captured a suspected member of one of these groups in the vicinity of the area where troops have amassed awaiting their final move into special demobilization zones. He was handed over to delegates of a UN-led mission set up to verify the ceasefire and concentration of Farc troops.

Under the peace deal, a revised version of which was signed on 24 November after the original was rejected in an October referendum, all the Farc troops are to relocate to one of 27 special demobilization zones. They will hand over their weapons to a UN commission by late April and become a legal political party.

The constitutional court on Tuesday ruled that congress could use fast-track authority to pass laws implementing the accords, the first of which will be a blanket amnesty for rank and file rebels not directly responsible for war crimes.