A controversial cross-border raid into Ecuador by Colombian troops at the weekend is unlikely to lead to war in the region — but it is a huge setback to peace and hopes for the release of hundreds of hostages being held by left-wing rebels.

At least 17 Farc guerrilla’s died in the daring night raid on a clandestine camp a few hundred feet inside Ecuadorean territory. Details remain sketchy, but the raid on Saturday appears to have targeted Luis Edgar Devia, 59 (better known by his alias, Rául Reyes), one of the top three leaders of the Farc, Colombia’s main left-wing guerrilla army that has waged war against the state for four decades.

The raid highlights potentially explosive tensions between Colombia and its neighbours over the Farc’s use of porous borders to smuggle cocaine in return for weapons, as well as using foreign soil for rest and recuperation camps.

The raid was hugely popular with most Colombians, who deeply detest the Farc’s often brutal tactics. The Colombian military says that Reyes’ laptop contains evidence suggesting that the Ecuadorean Government knew and tolerated the presence of the rebel camps on its territory and was willing to post sympathetic military officials to the region.

Colombia also accused Hugo Chávez, the Venezuelan President, of providing Farc with $300 million (£150 million) in financial support.

This alleged collusion is hardly a surprise. Chávez has openly expressed his sympathy with Farc, recently calling on the rest of the world to recognise the group’s legitimate belligerent status. Farc is officially labelled a terrorist group by Europe and the United States because of its involvement in drug trafficking and kidnapping, making it illegal for left-wing groups to raise fund or otherwise provide support for them.

Reyes was also one of the most familiar faces of Farc, acting as its chief spokesman and peace negotiator, so it was not unusual for him to have contact with foreign governments. The attack puts Alvaro Uribe, the Colombian President, in an awkward situation. He is already under enormous pressure to negotiate the release of several prominent hostages held by the Farc, including three American defence contractors and a French-Colombian former presidential candidate. Reyes had been one of the main points of contact in the hostage talks, with both the Venezuelan and French governments.

The Colombian Government said on Saturday that Devia was killed in heavy combat between rebels on the Ecuadorean side of the frontier and Colombian troops on the other. Colombian jets were called in to bomb the rebels and a commando team then crossed the frontier to recover the bodies of Devia and another rebel commander.

Uribe has apologised to Ecuador for the incursion, saying that it was a legitimate act of self-defence. But Ecuador says evidence at the scene indicates that the rebels died in their sleep, suggesting that the raid was not a case of hot pursuit but a premeditated incursion.

“They were bombed and massacred while they slept using pinpoint technology that found them at night, in the jungle, for sure with the collaboration of foreign powers,” said Rafael Correa, Ecuador’s president, hinting at US-supplied satellite technology and eavesdropping equipment.

The likelihood of war remains remote, analysts say, given the vital commercial ties that bind Colombia with both Venezuela and Ecuador. Venezuela is Colombia’s second largest trading partner with $3 billion in two-way commerce. “The crisis is going to escalate and will drag on for months, but it has to be seen within this commercial context,” said Bruce Bagley, a veteran Andean expert at the University of Miami.

So far, Ecuador has expelled Colombia’s ambassador and withdrawn its ambassador from Bogotá. Chávez also described the raid as a “cowardly assassination”. He has shut down Venezuela’s Embassy in Colombia and sent ten army battalions to the border. In his weekly TV show on Sunday, Chávez told Uribe: “If you decide to do this in Venezuela, pal, we’ll send you a few Sukhois,” referring to Venezuela’s newly acquired Russian fighter jets.

The raid in the early hours of Saturday was conducted with rare military precision and is seen by analysts as a sign of greater mobility and tactical skill by Colombia’s armed forces after a decade of US training and finance.

Reyes’ death comes on top of a series of military setbacks in recent years for the Farc, which has been forced to retreat into more remote, rural areas while its ranks have shrunk to about 10,000 because of combat deaths and desertions. It remains by far Latin America’s largest guerilla organisation, controlling large swaths of jungle, while financing its military logistics with drug trafficking and hostage-taking. But the Farc enjoys only marginal support in Colombia these days. Any romantic notion of revolutionary struggle evaporated years ago, especially after the Farc involved itself in the drug trade and in mass hostage-taking, as well as gruesome civilian massacres. The Farc’s raison d’être is even weaker today after the widespread demobilisation of a brutal right-wing paramilitary apparatus that was the rebel’s principal enemy.

Times Recommends

• Obama: the world can expect better of America
• Gulp! Mystery killer threatens French oyster
• Secret of Northn Lights key to space safety