President Santos has suspended indefinitely peace talks between the 4,000-strong National Liberation Army (ELN) and the Colombian government after the guerrilla detonated a bomb in front of a police station in Barranquilla, Saturday, killing five agents and wounding several dozen.

The ELN confirmed they had orchestrated the attack on Twitter, claiming it was a “response” from their Urban War Front (Frente de Guerra Urbano Nacional), against the “refusal of the national government to find solutions to the civilian population.”

On Monday, Colombia’s National Police confirmed the arrest of one of the alleged bombers.

“I have taken the decision to suspend the installation of the talks scheduled for the next several days until I see coherence on the part of the ELN, between words and actions,” said Santos, during a visit to La Palma, Cundinamarca, Monday, to oversee a land restitution program.

Colombia’s Defense Minister Luis Carlos Villegas confirmed the “authorship” of ELN’s “terrible actions.”

The indefinite suspension of the talks, comes more than two weeks after the fifth round of talks were scheduled to start, then were abruptly halted on January 10, after a front of the armed insurgency launched a series of attacks against the country’s main oil and gas pipeline Caño Limón-Coveñas, and a soldier from an army garrison in Arauca was shot during an ambush.

Santos proceeded to recall the government’s chief peace negotiator with ELN, Gustavo Bell, to Bogotá.

The attack was perpetrated hours after a 101-day bilateral cease-fire had ended, casting into doubt the future of a negotiated settlement with a guerrilla founded by rouge Catholic priests, back in the 1960s.

The collapse of the agreed-upon truce has been followed by an intensification of the armed conflict.

Foreign governments have called on the ELN to show restraint and shortly after the first visit to Colombia by the United Nation Secretary General Antonio Guterres the guerrilla, from Quito, did express their “readiness” and “willingness to seek solutions to the impasse created by the government.”

But, Santos has insisted ELN show real gestures of peace, rather than “just talk.”

The negotiations were on the verge of resuming last week when Gustavo Bell returned to  Quito. Brazil, Chile, Cuba, Ecuador, Norway and Venezuela are guarantor nations of talks that formally began in February 2017.

While international organizations are committed to accompanying the process, a report last month by Human Rights Watch condemned ELN for attacks against civilians and their continued use of kidnapping for economic and political gain. “In 2017, ELN continued to commit serious abuses, such as executions, forced displacements and recruitment of minors in the department of Chocó. On October 25, ELN murdered an indigenous leader in Chocó, despite having committed to the government to stop these abuses.”

On Saturday, Santos headed to Barranquilla to visit the wounded policemen and console the families who lost loved ones in the blast against the San José station, remarking: “Rest assured, all those responsible will face justice.”

President Santos had just returned from attending the World Economic Forum in Davos, Switzerland, when the latest attack by ELN rocked a northern suburb of this important Caribbean port. Barranquilla is preparing to receive tourists from around the world next month when it celebrates its legendary carnival.