US President Donald Trump has blamed the FBI for failing to stop leaks to the media.
He said the information being reported is classified and could have a "devastating effect" on the country.
Mr Trump made the remarks in a tweet early on Friday.
His tweet followed reports that White House chief of staff Reince Priebus had asked a top FBI official to dispute media reports that Mr Trump's campaign advisers were frequently in touch with Russian intelligence agents during the election.
Mr Trump tweeted: "The FBI is totally unable to stop the national security 'leakers' that have permeated our government for a long time. They can't even find the leakers within the FBI itself."
He added: "Classified information is being given to media that could have a devastating effect on U.S. FIND NOW."
find the leakers within the FBI itself. Classified information is being given to media that could have a devastating effect on U.S. FIND NOW— Donald J. Trump (@realDonaldTrump) February 24, 2017