DENVER -- The Colorado Bureau of Investigation has identified the person who leaked confidential information from a federal database that was used in an attack ad aired by GOP gubernatorial candidate Bob Beauprez, 7News reported.

Law enforcement sources told 7News that a federal law enforcement officer in Denver was identified as the person who accessed the database.

The officer, who has not been publicly identified, has retained a lawyer and has refused to speak with investigators, 7News reported. His career is in jeopardy, 7NEWS reported.

The Beauprez campaign said the information came from a credible source. Sources told 7NEWS that the source is not in the FBI because the FBI is now involved in the investigation.

The question is how the information got to the Beauprez campaign and if the campaign knew that laws were being broken.

The attack ad blasts Democratic candidate Bill Ritter for allegedly being soft on crime, turning a heroin dealer, Carlos Estrada Medina, loose to prey upon others, including a child in California.

The connection between the two crimes was made by a federal agent using the Crime Information Center, a secure federal database available only to law-enforcement officials, 7NEWS reported.

"Because this is a federally controlled and regulated system, CBI has requested the assistance of the FBI to further pursue the investigation," said CBI Director Robert Cantwell. "The FBI and CBI will be working jointly to complete the investigation."

On the campaign trail on Thursday, Ritter told 7NEWS that Beauprez should come clean.

"This is a perfect opportunity for him to be accountable by telling us who his source was and whether that source has any connection to the illegal activity," said Ritter. "The Congressman needs to reveal the source of the information. He's asking people to hold him accountable, this is the perfect opportunity."

The Beauprez campaign said that the ad is accurate and they are cooperating with investigators.

"We're trying to bring this to resolution as quickly as we can because this should be a law enforcement issue, not a political sideshow," said John Marshall, Beauprez's campaign manager. "The campaign's done nothing wrong. We are fully cooperating. We have given them everything they asked for and more."

Use of the federal criminal database for any purpose other than law enforcement is a crime punishable by fines and up to a year in prison.

The ad said that when Ritter was the district attorney for Denver he agreed to a plea bargain with Medina and that Medina was not deported. Medina was later arrested in California on suspicion of sexually assaulting a minor, the ad says.

Medina used an alias in arrest databases maintained by Colorado and California but a federal NCIC number was used to connect his alias to his real name, Ritter's campaign said.

Ritter's campaign had suggested that the information came from confidential federal records and demanded that Beauprez explain how it was obtained.

"If calling in the FBI will bring a quicker resolution, fantastic," Ritter spokesman Evan Dreyer said Wednesday. "Right now we're getting zero accountability from (Beauprez)."

The Beauprez campaign has said the information came from an informant and has refused to identify the source.

The FBI's involvement "doesn't change anything for us," Marshall said. "We're going to fully cooperate with whomever we need to cooperate with."

Gov. Bill Owens had asked the CBI to expedite the investigation. Lance Clem, spokesman for the state Department of Public Safety, which oversees the CBI, said the investigation may take a week or more.

It's unclear whether the investigation will be resolved before Election Day.

In a debate on the radio on Wednesday, Beauprez said that Ritter was just trying to dodge questions about why he plea-bargained with the defendant mentioned in the ad.

"I think, in fact I know, that the information we've got is absolutely, indisputably true. I understand why Bill wants to change this subject. He doesn't want people to know who he put back on the streets, that he put a heroin trafficker back on the street who a short time later assaulted, sexually assaulted, abused, whatever the legal term is ... a young, teenage child in California," Beauprez said.

Beauprez, who represents Colorado's 7th Congressional District in the north Denver area, and Ritter are vying to replace Owens, a Republican who cannot run again because of term limits.

The ad refers to a suspect arrested in Denver in 2001 on suspicion of heroin trafficking and later in California on suspicion of sexual assault.

Reporters found that the person arrested in Colorado was listed under a different name and date of birth than the man arrested in California, according to the Ritter campaign. When questioned, the Beauprez campaign said it was the same person because federal criminal databases carried the same FBI numbers in both cases.

Dreyer said the Ritter campaign tried verifying that information through public records but could not, raising the possibility that the databases were illegally accessed.