At first, Sandra Gonzalez didn't think much of the guerrillas burying objects on the dirt road outside her isolated, cinder-block farmhouse as they prepared to leave town 12 years ago.

But soon cows and horses began to die, ripped apart by exploding land mines. Then a neighbor lost his life. From then on, neither Gonzalez nor her four children have dared to turn right walking out the door.

"When the livestock escaped from the corral, nobody would chase after them," Gonzalez said.

Tens of thousands of land mines are among the most sinister scars of Colombia's half-century conflict. And even as the government and rebels hold slow-moving peace talks in Cuba, more are being planted, perhaps faster than old ones can be removed.

Dressed head to toe in an astronaut-like armored suit, soldier Albeiro Jose Acuna kneels on the ground combing for explosives. Minutes feel like hours as the army technician advance centimeter by centimeter with a paint brush and tweezers to inspect every suspect object before declaring it safe to tread. Information about the exact location of the mines is scarce to nonexistent.

"Any small mistake can take your life," says Acuna. A bead of sweat dripping from his face, less from the tension, he says, than the suffocating heat in this jungled valley a few hours from Medellin, Colombia's second largest city. "This is no place to be nervous."

Colombia is the world's second-deadliest country for land mines, behind Afghanistan, with more than 2,000 people killed and 11,000 maimed or wounded by shrapnel since 1990, according to the government. About a third of the victims are civilians.

Most of the hidden killers were planted by retreating members of the Revolutionary Armed Forces of Colombia as part of a strategy to protect themselves from pursuit by sowing terror in the minds of their battlefield enemies.

For at least a decade, an army battalion, now commanded by Col. Andres Goyeneche, has been in an uphill struggle to remove mines in areas no longer contested by the rebels.

Goyeneche said the battalion has removed 4,400 mines so far, but according to government estimates, at the current pace and with the technology available, it would take 47 years to certify Colombia is clear of land mines even if no more are planted.

For every explosive that is removed, at an estimated cost of $1,000 per device, several more are assembled using cheap, readily available materials such as coffee tins, fertilizer and syringes, he said.

"Every guerrilla can carry four or five (explosives) in their backpack," he said. "There are ones that detonate with movement, others covered in excrement so dogs can't detect them, and they're even placed inside soccer balls. ... You can make mines in as many ways as your imagination allows you to spread evil."

The FARC have promised to stop using land mines, something Colombia's army did in 2000 when it signed an international treaty.

But though their use has decreased, the weapons continue to be part of the rebels' arsenal. Just last month, more than 400,000 people in the port city of Buenaventura went four days without electricity after rebels blew up a transmission tower and then fenced the wreckage with land mines, making it impossible for work crews to enter.

The attack and others like it have been turning Colombians against peace talks in Cuba. For the first time since the start of negotiations three years ago, support for a military solution to the conflict now surpasses backing for the talks, according to a Gallup poll last month.

An agreement on land mines struck in March was supposed to breathe life into the talks, building trust among longtime adversaries and providing the first tangible benefit for poor communities like Granada that have been torn by years of war, massacres and neglect by a distant government.

The government and rebels agreed to work side by side to remove mines in 786 municipalities, about half the total nationwide, where explosions have been reported. While rebel and military commanders have met before news media cameras to symbolically prepare for the effort, progress is slow going and the pilot project has yet to begin in earnest.

Goyeneche said he is skeptical of the rebels' pledge.

"If the FARC really wanted to help instead of taking photos, they'd stop planting mines," he said.

Farmer Alirio de Jesus is more willing to give it a try. Sitting in the town's plaza, he takes off his shirt to show the burns from a mine blast a decade ago.

"I was walking when all of a sudden I went flying through the air," said de Jesus, who was left bleeding for hours until someone came to his rescue.

"A day after the land mine exploded, a neighbor was also killed nearby. Then a week later a cousin of mine and then another neighbor the next month," he said.

Despite his injuries, de Jesus said he will forgive the rebels if that's the price for peace.

"Forgiveness is the only way to make way for a lasting peace for everyone," he said.