A counter-terrorism analyst at the US Defense Intelligence Agency pleaded guilty on Thursday to leaking secret information to journalists, including details about foreign countries' weapons systems.
Henry Kyle Frese, 31, who was arrested in October, faces a maximum of 10 years in prison when he is sentenced in June, the Department of Justice said in a statement.
It detailed how Frese had leaked information to two unnamed journalists, one of whom he lived with, in 2018 and 2019.
One news outlet, which was also not named, published eight articles containing classified information.
Frese searched restricted government computer systems at least 30 times in 2018 for information to pass on verbally to the two journalists.
He also sent some secret information via private messages on social media, the Department of Justice said, citing court documents.
"He alerted our country's adversaries to sensitive national defense information, putting the nation's security at risk," Assistant Attorney General for National Security John Demers said.
"Disclosing such information for personal gain, or that of others, is not selfless or heroic, it is criminal."