Secretary of Defense Pete Hegseth issued stricter orders on Friday for journalists accessing the Pentagon building, as the Trump administration places further restrictions on the press.The new rules ban credentialed reporters from most of the Department of Defense headquarters in Arlington, Virginia, without official approval and escort, Hegseth said in a memorandum.Hegseth described the protection of classified national intelligence information and sensitive unclassified information on operational security as "an unwavering imperative for the Department.""While the Department remains committed to transparency, the Department is equally obligated to protect [Classified National Security Information] and sensitive information - the unauthorized disclosure of which could put the lives of U.S. Service members in danger," the secretary said.PENTAGON STOPPING GENDER TRANSITION TREATMENT FOR TRANSGENDER TROOPSHegseth's order will also soon require members of the Pentagon press corps to sign a form acknowledging their responsibility to protect national intelligence and sensitive information. Journalists will also be issued new badges that clearly identify them as members of the press."We also anticipate a forthcoming announcement of additional security measures and enhanced scrutiny on the issuance of [credentials]," the memo said. "Failure by any member of the resident or visiting press to comply with these control measures will result in further restrictions and possibly revocation of press credentials."The Pentagon Press Association, a membership organization representing the press corps covering the U.S. military, said the new rules seem to demonstrate a "direct attack on the freedom of the press."BIPARTISAN BILL WOULD MAKE IT EASIER FOR MILITARY RECRUITS WITH MEDICAL ISSUES TO LAND DEFENSE JOBS"The decision is purportedly based on concerns about operational security," the group said in a statement. "But the Pentagon Press Corps has had access to non-secured, unclassified spaces in the Pentagon for decades, under Republican and Democratic administrations, including in the aftermath of the Sept. 11, 2001 attacks, without any concern about OP-SEC from DoD leadership."Last month, the Pentagon fired three officials after announcing a leak investigation in March at the Department of Defense.The Pentagon has also required legacy news outlets, including The New York Times, The Washington Post, Politico, NPR, CNN and NBC News, to vacate their office spaces in the building as part of a new rotation system to bring in other outlets, most of which are generally more friendly to the Trump administration, including the New York Post, Breitbart, the Daily Caller and One America News Network.The department said the rotation system aimed to allow other media outlets the opportunity to cover the Pentagon as resident members of the press corps.Additionally, the administration has begun using lie detector tests to probe unauthorized leaks at federal agencies. Some Department of Homeland Security officials were told they could be fired for refusing polygraphs.The White House said Trump will not tolerate leaks to the media and that federal employees who leak material should be held accountable.Reuters contributed to this report.