Gunmen in a coastal Colombian city killed a former right-wing paramilitary leader who objected to the militia's involvement in drug trafficking, police said Sunday.

Carlos Mauricio Garcia, known by his nom de guerre, Rodrigo 00, was shot in the head five times as he left a Santa Marta supermarket Friday night, police Col. Oscar Gamboa said. No arrests have been made.

In an e-mail to the Associated Press earlier this month, Garcia said drug traffickers within the paramilitary group led by Diego Fernando Murillo wanted him dead.

"You can use my name," he wrote. "Because what else can happen to me? Will they want to kill me more times, or with more intensity, or with a bigger gun?"

Garcia's killing comes one month after the disappearance of Carlos Castano, the former top commander of the paramilitary umbrella group known as the United Self-Defense Forces of Colombia, or AUC. Castano, who is presumed dead by many of his colleagues, is wanted in the United States on drug trafficking charges.

The paramilitary groups emerged in the 1980s -- financed by ranchers and drug traffickers and backed by Colombia's military -- to fight leftist guerrillas, including the country's main rebel group, the Revolutionary Armed Forces of Colombia, or FARC. The paramilitary fighters became notorious for committing massacres and became deeply involved in the cocaine trade.

Garcia led the Metro Bloc, a paramilitary faction based in Medellin, which battled leftist rebels in poor neighborhoods in Colombia's second-largest city. He later split with the main paramilitary group.

[In an interview with The Washington Post in July 2003, Garcia said he believed the U.S.-backed Colombian government had misjudged the paramilitary movement and might agree to a peace accord with an organization that had no intention of giving up its most profitable enterprise: drug trafficking. Garcia warned that the group would use peace negotiations to gain political legitimacy and to escape prosecution with its huge profits intact.

[Like many paramilitary commanders, Garcia was once a Colombian army officer.]