WASHINGTON >> The Drug Enforcement Administration is investigating a former agent who was previously stationed in Colombia for misconduct, a U.S. law enforcement official said today.

The former agent, Jose Irizarry, abruptly quit his position at the DEA and is suspected of passing information to Colombian drug traffickers, according to BuzzFeed News, which first reported the investigation.

“The matter remains ongoing within the DEA disciplinary system, and we cannot comment at this time,” said Melvin Patterson, an agency spokesman.

The allegations against Irizarry could make it more difficult for U.S. law enforcement officials to earn the trust of confidential informants in the shadowy world of drug trafficking. In some Latin American countries like Colombia, where cartels rule with force, cooperating with law enforcement almost certainly spells a death sentence.

Informants are a critical tool for U.S. law enforcement officials working to untangle transnational drug trafficking. But their ability to protect those informants has come under scrutiny in recent years.

Congressional Democrats have called for an investigation into DEA-led operations in Mexico, in which information passed from U.S. officials to Mexican authorities was said to have been shared with cartel leaders, prompting two violent attacks.

A DEA officer in New Orleans is facing charges of perjury, obstruction and a swath of other accusations in a wide-ranging scandal that saw members of a DEA task force plead guilty to stealing drugs and cash during federal raids.

The largest producer of cocaine in the world and the United States’ lead supplier, Colombia is a key operating ground for those officials seeking to dismantle drug trafficking networks. As a party to those efforts in Colombia, Irizarry was in a uniquely sensitive position.

Cocaine use has surged in recent years in the United States, where 92 percent of cocaine seized by federal authorities in 2016 was traced back to Colombia. The DEA said last fall that the U.S. demand for cocaine was rising to levels not seen in almost a decade, and production of the drug in Colombia was the highest ever observed.

Calls to a number believed to be Irizarry’s in Florida were not answered. The extent of the information Irizarry is alleged to have passed to drug traffickers could not be determined.

In 2015, an internal Justice Department watchdog accused DEA officers in Colombia of attending sex parties paid for by drug cartels over a period of several years. Seven agents admitted to the misconduct and were suspended. That scandal roiled the agency’s headquarters, prompting the resignation of its administrator, Michele Leonhardt.

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