The last chord is hit and smoke floods the stage. The spotlights go crazy, the crowds go crazy, and the rocker thrusts his electric escopetarra into the air. "This is about transformation," César López will explain later, backstage, strumming the strange-looking instrument. "It's about turning something bad into good.... It's about possibilities."
More than 100,000 Colombians have been killed here during 40 years of conflict and a civil war continues to rack the country, pitting leftist guerrillas and right-wing paramilitary forces against both each other and the government.
The past four years under newly reelected President Alvaro Uribe have not ended the bloodshed, but they have seen some advances. Following negotiations with the paramilitaries and initial talks with some of the guerrillas, 39,580 illegal combatants have demobilized, laying down approximately 17,000 weapons, according to President Uribe's office.
The weapons these fighters turn in – Galils, Winchesters, AK-47s, and more – are taken into custody by the attorney general's office and stored in military bases. Some of them will eventually be melted down. Others will be reissued to the police and army.
And a small number of them will become guitars.
An escopetarra is part shotgun (escopeta) and part guitar (guitarra) – with the barrel running through the neck of a guitar, strings mounted near the butt of the rifle, and an amplifier hooked into where the trigger might be.
"We grew up with conflict but we are sick of it," says Mr. López, the musician who invented the first escopetarra. López's older sister, a guerrilla, was captured in the 1970s and, he says, tortured. "That made a big impression on me. It made me want to figure out how this country would ever be OK."
The idea for the escopetarra came to him several years ago. Together with a group of musician friends, López had established an artistic "rapid response battalion," that would show up at scenes of attacks in Bogotá to play free concerts for the victims.
It was February 2003 and López was racing to the scene of a bombing at a social club – an attack that killed 30 people – when his way was blocked by a young soldier holding a rifle.
"I was standing there with my guitar, across from the soldier, and I looked at our stances and realized they were identical," López recalls. "I thought about it, and then went to the military to explain my vision and try and get them to give me guns to turn them into guitars. They thought I was a wimp and a hippie and said no."
The mayor of Bogotá, who was running his own local disarmament program at the time, was more amenable to the idea, and gave the musician five heavy Winchesters that had been handed in by leftist rebels. Several designs, five weeks, and $800 later, the first escopetarra came into existence.
It was an immediate hit, with Colombian rock stars lining up to use it and youngsters' adopting it as an antiwar symbol. So far, only five such instruments exist because, explains López, of the difficulty in procuring the arms. The authorities often need to hold on to the weapons for evidence in potential trials.
It is estimated that 2 to 3 million illegal weapons are floating around Colombia. The FARC, Colombia's largest and strongest guerrilla group, has refused to negotiate with the government or to disarm. Furthermore, it is generally believed that even those groups who do disarm – such as the paramilitaries – do not hand in all their weapons. Perhaps most significantly, the billions of cocaine dollars a year streaming into the country means that the groups can easily rearm.
"Regardless of massive efforts on the parts of governments, embargoes, and UN efforts ... if you have money, you can get arms," says Moises Naim, author of "Illicit: How Smugglers, Traffickers and Copycats Are Hijacking the Global Economy." "Top members of the organization ... have access to cocaine money, and can easily place a new order for anything from bullets to rocket launchers."
The FARC are "rich terrorists," says William Wood, US ambassador to Colombia. "They don't steal weapons, they buy them. The number of weapons turned in is important. But still, we all know the bad guys have money to buy more."
Many of these new arms, says Marta Lucia Ramirez, a former Colombian defense minister, stream in through the porous borders of Venezuela and Ecuador. When Salvatore Mancuso, commander of the country's largest and most brutal right-wing paramilitary group, disarmed last year his personal pistols were traced back to Venezuela. The US last month announced it planned to stop selling arms to Caracas because of such reported transfers.
In this context, it is clear the invention of the escopetarra will have little effect on the number of arms in circulation, admits López. But, he stresses, symbolism is a strong weapon, too.
The UN has commissioned an escopetarra to display at its upcoming UN Conference on Arms scheduled later this month. The Museum of Modern Art in New York has shown interest in purchasing one, and Colombian rock star Juanes recently auctioned off his personal escopetarra in Los Angeles for $17,000 to benefit victims of land mines. López meanwhile has just been made a UN goodwill ambassador and in January he received two AK-47s that will be turned into escopetarras for the musician Shakira and Mexican pop artist Juliet Venegas.
And in light of the growing wave of international appreciation for the escopetarra project, the military seems to have changed its tune about "hippies." This week, it is scheduled to give 12 AK-47s to López. "Progress is slow," he admits, putting down the escopetarra and getting ready to go home, "...but at the end we will have a whole escopetarra rock band strumming."
• Ms. Harman is Latin America correspondent for the Monitor and USA Today.