President Trump’s administration issued subpoenas on Friday to some New York Times journalists after the newspaper’s report this week on alleged security concerns involving the new Air Force One, according to the paper.

The subpoenas seek to force the reporters to testify before a federal grand jury in Manhattan on Wednesday, the paper said, adding that federal agents delivered some subpoenas to the reporters at their homes.

The Times’ report about the subpeonas could not be independently confirmed and there was no immediate response from the White House or the Department of Justice.

“The appearance of federal law enforcement agents on the doorstep of news reporters should shock the conscience of any American who believes in the Constitution and the press freedom it protects,” said the paper’s lawyer David McCraw in a statement Friday.

The developments come after the president flew the new Air Force One to a NATO summit in Turkey. But he departed Wednesday on one of the older-model Air Force One jets for a trip to Mildenhall, a Royal Air Force base in Suffolk, England. The two jets both flew to Mildenhall. Mr. Trump then switched to the newer plane for the flight home to Joint Base Andrews.

The plane swap came as a shaky ceasefire with Iran had collapsed, with the U.S. launching airstrikes on Iran and Tehran attacking three Gulf Arab states.

The paper reported Wednesday the switch had come at the urging of the Secret Service. On Thursday, the paper said the newer plane lacked some of the advanced security features of the older aircraft, including antimissile capabilities. Both articles cited anonymous sources. 

CBS News also reported that the Secret Service advised Mr. Trump use the old jet. U.S. officials told CBS News that the new plane was hurried into service and is lacking some desired capabilities, and a former U.S. government official who spoke to CBS News expressed concern that there wasn’t enough time or money to outfit the new plane with defensive capabilities to fully meet the requirements to serve as Air Force One.  

Mr. Trump, at the time, denied any security concerns, posting on social media that the stop in Mildenhall was so that service members there could view the new jet. During the flight, the president denied to the reporters accompanying him that security concerns involving Iran were a factor in flying two planes home. Asked if he was aware of any credible threats against Air Force One by Iran, Mr. Trump brushed off the question.

“I have a threat all the time. I’m No. 1 on their list,” he said

The White House later denied any security shortcomings on the new plane. Spokesman Steven Chung said in a statement that the new plane “is a state-of-the-art aircraft that has been fitted with high-level security protocols that ensure the safety of the President and his staff.”