Attorney General Pam Bondi said the search was part of an investigation into an alleged leak from the Pentagon, which has introduced new restrictive media policies under President Donald Trump.

Bondi said the journalist "was obtaining and reporting classified and illegally leaked information from a Pentagon contractor" and that the search warrant was executed after a request from the Defense Department.

The Post named the reporter as Hannah Natanson and said federal agents seized a work laptop, a personal laptop, her phone and a watch from her home in Virginia, outside Washington.

Agents told Natanson she is not the focus of the probe.

The paper reported that law enforcement was investigating Aurelio Perez-Lugones, a system administrator with top-level security clearance who is accused of taking home intelligence documents found in his lunchbox and his basement.

Perez-Lugones, who served in the US Navy before working as a Pentagon contractor, was arrested last week in Maryland, according to court documents that do not mention any contact with journalists.

"The leaker is currently behind bars," Bondi said on social media. "The Trump Administration will not tolerate illegal leaks of classified information that, when reported, pose a grave risk to our Nation's national security."

In December, Natanson wrote how she posted her secure phone number on an online forum for government workers and many contacted her about their experiences of radical cutbacks and policy changes in Trump's second term.

The Defense Department last year restricted media access inside the Pentagon, forced some outlets to vacate offices in the building and drastically reduced the number of briefings for journalists.

US and international news outlets including The New York Times, AP, AFP and Fox News declined to sign the new media rules and were stripped of their press access credentials.