The seal of the Department of Homeland Security. (Salwan Georges/The Washington Post)

The actions of a Customs and Border Protection agent who confronted a reporter covering national security issues about her confidential sources are being examined by the CBP’s Office of Professional Responsibility, the agency said in a statement Tuesday.

The agent, Jeffrey A. Rambo, contacted journalist Ali Watkins last June as the Trump administration was ramping up its investigations of unauthorized leaks to reporters, and he identified himself as a government agent.

Rambo met with Watkins at a restaurant in Washington after initially contacting her by email. A reporter taking such a meeting with a potential source would not be unusual.

But after he arrived, Rambo said the administration was eager to investigate journalists and learn the identity of their confidential sources to stanch leaks of classified information. He questioned Watkins broadly about her reporting and how she developed information, according to the people familiar with the incident, who spoke on the condition of anonymity to discuss a sensitive matter.

Rambo’s behavior was un­or­tho­dox. It’s highly unusual for government investigators to question reporters about their sources, and national security leaks are generally investigated by the FBI, not CBP, part of the Department of Homeland Security. Rambo also contacted Watkins using a personal email address and declined to provide his name.

Rambo asked Watkins, then a reporter at Politico, about her relationship with James Wolfe, then the director of security for the Senate Intelligence Committee. He gave her accurate dates and destinations for trips the two had taken together overseas — a revelation that left Watkins rattled, a person familiar with the events said.

Last week, the Justice Department indicted Wolfe on three counts of lying to FBI agents who were investigating the source of classified leaks to the media.

As part of the investigation, law enforcement officials seized years of Watkins’s phone and email records. Watkins, who is now a reporter at the New York Times, was in a years-long romantic relationship with Wolfe, which has since ended, a fact she disclosed to the Times when she was hired. She has also told the paper that Wolfe was not a source of classified information for her reporting.

Watkins did not respond to a request for comment, and her attorney, Mark J. MacDougall, declined to comment.

A spokesman for CBP, where Rambo works, said the agency “takes all allegations of employee misconduct seriously. The allegation has been immediately referred to CBP’s Office of Professional Responsibility. We encourage all members of the public to report any potential misconduct immediately so that it may be investigated.” The agency took action after The Washington Post inquired about Rambo, who declined to comment.

Rambo was not part of the FBI’s investigation of Wolfe, according to a law enforcement official who spoke on the condition of anonymity to discuss an open investigation.

Rambo’s search of travel records could be a crime if he didn’t have a legitimate reason to examine that information, which is protected by privacy laws and regulations that prevent unauthorized disclosures of personal information, officials said.

As a DHS employee, Rambo could have had access to records of when Americans leave and reenter the United States, including from the Advance Passenger Information System, first developed by U.S. customs officials in the 1980s.

The passenger records may be shared only with Homeland Security personnel “who have a need to know the information as part of the performance of their official employment duties,” according to a privacy assessment the department completed in 2015. The rules were put in place to keep government employees from inappropriately using Americans’ personal information.

Ethics rules also prohibit executive branch employees from improperly using “nonpublic information” to further their own — or someone else’s — interests.

At his meeting with Watkins, Rambo also had what appeared to be a sheet of information about Wolfe, as well as the Senate staffer’s current wife and his ex-wife, said one person familiar with the events.

Rambo also tried to enlist Watkins in his efforts, asking her to help the administration in its effort to crack down on leaks, the person said.

Julie Tate contributed to this report.