Mexico City, Mexico (CNN) -- A radio station in Mexico has aired parts of a telephone conversation it alleges took place between a top drug lord and a federal congressman.
In the recording, voices the station identify as those of lawmaker Cesar Godoy and Servando Gomez -- also known as "La Tuta," leader of the La Familia cartel -- express support for one another and discuss a wide range of topics including upcoming elections and a local reporter stirring up stories.
The tape has renewed concerns about corruption in a country struggling to subdue its powerful drug cartels. More than 28,000 people have died in drug violence in Mexico since 2006, according to authorities.
W Radio says the conversation took place more than a year ago and was collected as part of an investigation into Godoy's suspected cartel ties. The station did not disclose its source for the tape.
An official at the Mexican Attorney General's Office confirmed the recordings represent the real voices of Godoy and Gomez, but declined further comment.
"First of all, I want you to win. You have total support. You will win," the voice identified as Gomez' says in a conversation broadcast by W Radio.
The two male voices are heard talking about possible informants and a journalist who is said to be causing the congressman trouble.
Toward the end of the recording, the voice identified as Godoy's warns his friend: "Much care must be taken. This thing is heating up."
Godoy, who represents the state of Michoacan, already faces federal charges for allegedly helping the cartel, which is active in his area. He currently has immunity from arrest because of his status as a lawmaker, but he could lose that.
On Thursday, Godoy responded to the recordings, calling them part of a broad smear campaign.
Godoy, who was elected last year, failed to appear Friday at a congressional committee hearing meant to address his alleged cartel ties. He sent word his mother was ill and is now expected to appear Monday.
Thursday, he spoke briefly to reporters. He never specifically denied the voice in the recording was his. Godoy accused the government of leaking the tapes to discredit him. As it cannot prove its case against him in court, the government will try to win it politically, Godoy said.
"It all has to do with a political persecution against me," he said.