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Secret Service agent reportedly kills self after alleged affair revealed

A married Secret Service agent who died Saturday was facing administrative review for an alleged affair with a foreign citizen, officials tell NBC News. Local law enforcement sources say the agent killed himself.

Rafael Prieto, assigned to the security detail for President Barack Obama, had acknowledged to U.S. officials that he had been having an affair for years with a woman from Mexico, sources told The Associated Press. They spoke on condition of anonymity because they were not authorized to discuss the incident, the AP said.

A source with knowledge of the investigation told NBC News that one of the agents entangled in the prostitution scandal in Cartagena, Colombia, alerted the agency that Prieto was allegedly having the affair.

"Rafael Prieto had a distinguished 20-year career with the Secret Service that was marked by accomplishment, dedication, and friendships," spokesman Ed Donovan said in a statement. "The Secret Service is mourning the loss of a valued colleague."

A source with knowledge of the investigation told NBC News that Prieto was facing an administrative review, and that he was not under investigation for espionage or passing information to a foreign contact and was not under investigation by the Secret Service Office of Professional Responsibility.

Failing to disclose such a relationship would be a violation of the agency's administrative rules, not a crime, the AP reported.

Prieto was serving on the protective detail for Obama, though he was not on duty at the time of his suicide, the AP said. As recently as 2009, he was identified as the resident agent in charge at the Secret Service's office in White Plains, N.Y. He had worked for the Secret Service for 22 years. He was 47, according to public records.

Prieto's apparent cause of death was carbon monoxide poisoning. He was found in his car with the engine running. His death was being investigated by Metropolitan Police in Washington and the medical examiner's office.

The behavior of Secret Service agents and officers has come under scrutiny since 13 employees were implicated in a prostitution scandal in Cartagena, Colombia, in April.

Those employees were in Caribbean resort city in advance of Obama's arrival for a South American summit. After a night of heavy partying in some of Cartagena's bars and clubs, the employees brought women, including prostitutes, back to the hotel where they were staying. The incident became public after one agent refused to pay a prostitute and argued with her in the hotel hallway. Prieto was never in Colombia during the scandal.

Eight of those Secret Service employees have been forced out of the agency, three were cleared of serious misconduct and at least two employees are fighting to get their jobs back.

The scandal prompted Secret Service Director Mark Sullivan to issue a new code of conduct that barred employees from drinking within 10 hours of the start of a shift or bringing foreigners to their hotel rooms. 

This article includes reporting from NBC News' Kristen Welker and The Associated Press.

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