Ivan Marquez, a former leader of the Revolutionary Armed Forces of Colombia, FARC, center, speaks to the media as Victoria Sandino , left, and Pablo Catatumbo, right, listen to during a press conference in Bogota, Colombia, Tuesday, April 10, 2018. Seuxis Hernandez, a blind rebel ideologue best known by his alias Jesus Santrich, was picked up Monday at his residence in Bogota on charges that he conspired with three others to smuggle several tons of cocaine into the U.S. with a wholesale value of $15 million. (AP Photo/Fernando Vergara)

BOGOTA - When Colombia's largest rebel army turned over its weapons as part of a 2016 peace deal, its leaders vowed to walk away from a lucrative cocaine business that had fueled its war on the state decades after similar leftist insurgencies elsewhere in Latin America died off.

But the arrest of a high-ranking rebel leader on a U.S. drug trafficking warrant has many Colombians wondering whether the former guerrillas have betrayed their pledge.

A day after the arrest of Seuxis Hernandez, best known by his alias Jesus Santrich, conservative opponents of the peace accord, including the front-running presidential candidate, urged authorities to investigate other members of the disbanded FARC rebel army for any continued involvement in the drug trade.

"The message should be clear: Those with criminal ties should pay," presidential hopeful Ivan Duque said.

Meanwhile, ex-FARC combatants accused U.S. and Colombian officials of orchestrating a set-up against Santrich and warned it likely will sow further skepticism among former rebels already doubtful that the government will follow through on its end of the peace accord.

"It generates alarm," said FARC leader Griselda Lobo, alias Sandra Ramirez. "But we are calling on people to think with a cool head."

A U.S. indictment accuses Santrich and three others of conspiring to distribute 10 metric tons of cocaine with a wholesale value of $15 million in the United States and purporting to have access to drug labs and U.S.-registered planes for transport. U.S. officials allege the criminal activity began last year, after the established cutoff date giving most rebels immunity from war crimes.

The arrest makes Santrich the first high-ranking leader in the peace process to be charged with criminal activity, and analysts said it is likely to have a range of implications for the nation's already fragile implementation of the historic accord. Some worry Santrich's potential extradition could push already hesitant rank-and-file ex-combatants into the hands of criminal gangs.

"Some of them feel abandoned," said Juan Carlos Garzon, a research associate at the Ideas for Peace Foundation, a Colombia think-tank . "This reinforces a message that there is some uncertainty going ahead."

Dissident rebels still operating in FARC zones where the state has little presence are continuing to operate drug routes and are believed to be co-operating with Mexican drug cartels as Colombia's coca production skyrockets. There has long been speculation about whether former FARC have continued communication with dissident factions, though no evidence has been presented publicly to support it.

Jeremy McDermott, the Medellin-based executive director of InSight Crime, a group that studies organized crime in Latin America, said many ex-guerillas may fear a repeat of what happened to demobilized paramilitary commanders a decade ago, when more dozen leaders were extradited on drug charges by former President Alvaro Uribe after reaching a peace accord with the government.

"The guerrillas may well fear this is a potential future scenario for them," he said.

The FARC long funded their insurgency by levelling a "war tax" on cocaine moving through territory it dominated, and 50 members of its leadership structure — though not Santrich — were indicted in 2006 in the U.S. on charges of running the world's largest drug cartel.

But the rebels always denied direct involvement in the business itself and rebel peace negotiators in 2013 denounced drug trafficking as a "scourge" that has "contaminated" the international financial system and generated a global health crisis. The government has also credited them with implementing a crop substitution program aimed at providing an alternative livelihood to poor peasants growing coca.

The U.S. hasn't been so forgiving, however. Last year, it exposed 21 suspected drug traffickers wanted for extradition who had been put on the FARC's list of rebel fighters and sympathizers entitled to benefits under the peace deal. The rebels called it an error but never said how the alleged criminals ended up on their rolls, although many Colombians suspect they paid for the privilege.

Santrich, the son of two teachers, was one of the first rebel leaders to bet on peace, making his arrest all the more surprising. He went to Norway in 2012 to begin negotiations with Colombia's government and then participated in talks that continued the next four years in Cuba, where he earned a reputation as being a hard-line ideologue.

In recent months, Santrich had campaigned for a seat in congress and lived in a residence filled with his paintings. Despite being blinded by a hereditary illness, he had become a prolific artist, putting tacks in his canvases to guide the direction of his brush. Many of his paintings depicted FARC guerillas still being kept behind bars after the peace accord.

Despite the FARC's belief that Santrich is being wrongly victimized by U.S. and Colombian authorities, the group's leaders said they were committed to continuing the terms of the accord.

Nonetheless, they warned, it has left many ex-combatants wondering who might be next.

"This is grave for the implementation," Ramirez said. "And this is grave for our reincorporation."

News from © The Associated Press, 2018