BOGOTA (AP) -- A feared far-right warlord testified that murderous paramilitaries were created and used by Colombia's government to counter leftist rebels and that members of the current government had conspired with the group, witnesses said.

In explosive testimony Tuesday, Salvatore Mancuso said the state organized the fighters in the 1990s to retake the country's north from a well-entrenched, extortionist leftist rebellion.

Mancuso alleged that Defense Minister Juan Manuel Santos met with paramilitaries in order to plot an overthrow of the 1994-98 administration of disgraced ex-president Ernesto Samper. Santos was not a government official at the time.

The national daily El Tiempo reported that the warlord also said that he had personally met with Vice President Francisco Santos in the late 1990s to discuss the creation of a new paramilitary front in the country's capital. Francisco Santos was an editor at El Tiempo at the time.

Mancuso didn't provide any evidence to support these hitherto unknown allegations and neither Santos, who are cousins, could immediately be reached for comment. The chief prosecutor's office said it plans to investigate Mancuso's allegations.

"This statement ends the idea that the paramilitaries grew up and operated behind the backs of the political and military class," said Ivan Cepeda, director of the Victims' Movement, who heard Mancuso's statements.

Journalists were not allowed to enter the courtroom.

Mancuso, who once commanded the national organization of the paramilitaries, testified in the northern city of Medellin. His testimony fulfills in part a peace deal that requires demobilized militia commanders to confess their crimes in exchange for limited prison sentences.

Cepeda said Mancuso also testified that in exchange for the paramilitaries' help in exterminating the Medellin cartel and its capo, Pablo Escobar, the government of then-President Cesar Gaviria agreed to create legal vigilante defense groups to combat rebels.

Gaviria became secretary-general of the Organization of American States in 1994, a year after Escobar was killed in a police raid.

The vigilante groups, known as Convivir, were championed by President Alvaro Uribe when he was governor of northern province of Antioquia, and disbanded after their links to the paramilitaries were revealed.

Mancuso also detailed the ties the paramilitaries, whom the U.S. State Department branded in 2001 as a "foreign terrorist organization," had to many Colombian army generals.

He said top army brass helped the illegal militias in training and logistics. Demobilized paramilitaries have described joint operations between paramilitaries and regular army troops.

The paramilitaries originally were formed by landowners and drug traffickers to wrest control of the countryside from leftist rebels but degenerated into criminal gangs with the help of regional political bosses and the security forces.

They committed some of the worst atrocities of Colombia's long-running conflict as they expanded across the nation in the late 1990s, killing thousands and stealing millions of acres from peasants.

More than 31,000 paramilitaries have laid down their weapons as part of the peace pact, and their top commanders are in jail awaiting trial. Under the peace deal, the warlords can receive no more than eight years in prison.