The Justice Department has launched a formal anti-trust investigation into five major U.S. television networks for their actions during a court battle over whether several news outlets should have access to the White House despite angering President Trump.

While the five networks — ABC, CBS, CNN, NBC and Fox News — did not comment, press rights advocacy groups denounced the move.

“[S]ummoning antitrust authority, on top of the retaliatory actions the White House has already taken to bar certain outlets, is another and even more brazen attempt to try to intimidate journalists,” said Bruce Brown, the president of the Reporters Committee for Freedom of the Press.