It was a most unresidential spectacle: President Alvaro Uribe upbraiding the editor of Colombia's top news magazine on morning talk radio for rekindling a corruption scandal just weeks before he stands for re-election.

The magazine Semana had doggedly reported on allegations of fraud in Uribe's 2002 election victory, a conspiracy to assassinate leftist and union activists, and the leaking of sensitive information to drug traffickers and right-wing paramilitary groups.

Semana also reported that officials in the state security agency, known as DAS, allegedly plotted to destabilize the government of Venezuelan President Hugo Chavez.

All this comes ahead of May 28 presidential elections in which Uribe, Washington's top ally in South America, enjoys a comfortable lead in opinion polls, having made this notoriously violent country considerably safer for the average citizen.

Uribe's stern lecture to Semana's editor, Alejandro Santos, was considered by groups including Human Rights Watch to be a frightening attempt to muzzle the press in a country where journalism is already a very dangerous profession.

"This topic is so delicate that the reports gave grounds for rendering the government illegitimate," Uribe complained to Santos of the DAS scandal coverage. "The harm isn't to Alvaro Uribe. The harm is to the legitimacy of Colombian democracy, to a country that for the first time is beginning to see a bonanza of investment."

Uribe proceeded to exhaustively detail his 2002 vote counts from the Caribbean region where the alleged fraud occurred, resisting interruption by the radio show host.

Colombia's law-and-order president is known for losing his temper with reporters, and his impulsive nature was on display in a barrage of recent radio and TV appearances he initiated to defend his administration.

"I'm not going to allow accusations to stand that the government assassinated labor leaders or was implicated in a conspiracy against Venezuela or somehow allowed me to steal the 2002 elections," Uribe said in another radio appearance.

Yet Colombia's president left a series of key questions unanswered.

First, why did Uribe name the man at the center of the scandal, Jorge Noguera, to the post of consul-general in Milan, Italy, rather than order a criminal investigation after Noguera was forced to step down as DAS director in October?

Noguera lost the job after the first evidence emerged, in press reports, that DAS agents were providing favors to right-wing paramilitary leaders and drug traffickers, such as the alleged erasing of their criminal records. The paramilitaries are considered a strong base of support for Uribe, who initiated a peace process with them that has resulted in the demobilization of some 28,000 leftist rebels.

Former DAS information systems director Rafael Garcia, in jail on charges he deleted files on paramilitary leaders and drug traffickers, is the source of the damning new allegations against Noguera.

"Yes, there was a plan to destabilize the government of Venezuela and many people in the Colombian government are involved," Semana quoted Garcia as saying in a jailhouse interview.

Garcia refused to offer more details, saying he will tell investigators from the chief prosecutor's office or a foreign government once he's been guaranteed protection for his family.

Noguera, meanwhile, returned from Italy last week at Uribe's insistence and roundly denied Garcia's allegations even as the chief prosecutor, Mario Iguaran, named a special team of investigators to pursue the case

Noguera did admit, however, to having met several times with "Jorge 40," the top paramilitary chief in the Caribbean coastal region, where Noguera was a key operative in Uribe's 2002 campaign before being named to head DAS, the rough equivalent of the FBI and the U.S. immigration service.

Uribe said those meetings were related to the peace process, but critics including Ramiro Bejarano, a columnist and former DAS chief — whom Uribe has also publicly attacked — are demanding a more explicit explanation of what business the head of the government's intelligence agency had with the head of a brutal outlaw army.

"I think President Uribe is the voice of paramilitarism, in so far as by his hand he has sketched a little mafiosa republic," Bejarano wrote in a scathing column in El Espectador on Sunday.

For his part, the Americas director of Human Rights Watch, Jose Miguel Vivanco, expressed concern that Iguaran, a former deputy justice minister under Uribe, would have an extremely difficult time with his investigation.

"This case affects powerful interests, which will probably exert pressure to make sure that the truth does not come out," Vivanco said in a statement issued Sunday.