Colombian President Juan Manuel Santos lifted a monthlong suspension of aerial bombings against Revolutionary Armed Forces of Colombia (FARC) guerrillas on Wednesday after the armed group killed 11 soldiers and injured 19 others — a major violation of the rebels' pledge of a unilateral cease-fire that throws into doubt the future of peace talks.
The rebel attack occurred around midnight Tuesday in the volatile southwestern department of Cauca, when an army unit on a routine patrol was surprised by FARC guerrillas firing homemade explosives and grenades. A corporal and 10 others were killed during the ambush, the army said in a statement.
Santos condemned the attack and lifted the aerial bombing suspension, which his government had trumpeted as a major milestone in the effort to end a half century of fighting.
"Let it be very clear to the FARC — I'm not going let myself be pressured by vile acts like this," Santos, flanked by his top military commanders, said in prepared statement Wednesday en route to the combat zone, in a rural outpost called La Esperanza (Hope).
Colombians denounced the attack on social media and called on Santos to abandon the peace talks.
"Santos, don't betray us anymore," former President Alvaro Uribe, a fierce critic of the peace process, said on Twitter. "Don't justify the murder of our soldiers with this talk of war you want to end."
FARC negotiators in Cuba committed in December to a unilateral cease-fire to promote peace talks that have taken place on the island nation over the past two years, saying the group would fire weapons only if attacked by the armed forces.
While adherence to the FARC leadership's command has been less than complete, the latest attack is the most serious breach to date. It could destroy the momentum toward a deal, which has been building since November, when FARC shocked much of Colombia by releasing an army general whom it had inadvertently captured.
Last month both sides agreed on a plan to begin jointly removing the land mines that litter large parts of the countryside. Soon afterward, the government suspended all aerial bombings of guerrilla camps, an order that Santos extended this month.
Such good-faith gestures are seen as crucial in rallying support for a deal when some of the thorniest issues, such as whether rebel leaders will serve time in jail for atrocities and the fate of U.S. drug indictments against FARC's leadership, remain to be negotiated. The two sides have already reached deals on land reform and political participation for former rebels.
The latest attack underscores one of the biggest obstacles in the way of a deal: FARC leadership's lack of control over its estimated 7,000 troops still on the battlefield. That's especially true in turbulent areas like Cauca, where rebel commanders are known to be heavily involved in drug trafficking.
From Havana, the FARC commander known by his nom de guerre, Pastor Alape, said he was unaware of the circumstances that led to Tuesday's attack. But he blamed the incident on Santos' refusal to declare a bilateral cease-fire, something FARC has been urging since the start of negotiation. "It's urgent for the nation, something the entire country is waiting for," Pastor Alape said.
Santos rejected such an option, repeating that he would halt fighting only after a definitive final truce was struck. But he also avoided any hint he would walk away from negotiations amid the latest crisis.
"Acts like this demonstrate once again the need to accelerate the peace talks," he said.
Al Jazeera and The Associated Press