The U.S. Department of Defense made a formal referral to the Department of Justice after planning documents relating to the war in Ukraine leaked online.
Military documents containing sensitive information about U.S. and NATO material supporting the Ukraine military in their fight against Russian forces began appearing on social media.
"We are aware of the reports of social media posts, and the Department is reviewing the matter," Sabrina Singh, Pentagon deputy press secretary, said Friday morning.
Friday night, Singh said the DOD has made a referral to the DOJ regarding the leak.
UKRAINE WAR PLANNING DOCUMENTS LEAKED ONLINE, PENTAGON INVESTIGATING
"The Department of Defense is actively reviewing the matter, and has made a formal referral to the Department of Justice for investigation," Singh said.
The Washington Post reported Friday evening the DOJ has opened an investigation into the leak of classified DOD documents.
The DOJ didn't immediately respond to a request for comment from Fox News Digital.
UKRAINE PREPARES FOR RUSSIAN SPRING OFFENSIVE
Analysts claim that the documents appear to be slightly doctored and exaggerate Ukrainian casualties while downplaying the losses by Russian forces.
Mykhailo Podolyak, an adviser to Ukrainian President Volodymyr Zelenskyy, quickly dismissed the leak as part of Russian disinformation games.
"The published data are related exclusively to the information and operational game that the Russians started in order to introduce confusion, seize the initiative and discredit the very idea of offensive. It is obvious," Podolyak said.
"Firstly, by gaining access to real plans, you will not publicly admit it. To prepare in secret counter activities. And therefore, secondly, it is possible to organize a 'drain' of fictitious data only within the framework of a special informational counter-game," he added.
The documents leaked appear to be over a month old, dated from March 1.
Fox News' Timothy H.J. Nerozzi, Caitlin McFall, and Constance McDonough contributed to this report.