U.S. federal investigators arrested a 21-year-old Air National Guardsman on April 13, believed to be in connection with the massive U.S. military intelligence leak, the New York Times reported.
The New York Times has identified the suspect as Jack Teixeira, a member of the intelligence wing of the Massachusetts Air National Guard.
Attorney General Merrick Garland said that Teixeira was arrested "without incident" relating to the "unauthorized removal, retention and transmission of classified national defense information," the New York Times wrote.
The leak of U.S. military and intelligence documents was first spotted on the online media platform Discord.
The information in the leaked documents covers a range of issues relating to Russia's all-out war in Ukraine, including a prediction that the war will continue "well beyond" 2023.
According to one leaked document, Ukraine's air defense systems risk being depleted by mid-April and early May if they are not replenished, potentially increasing the risk of Russian airstrikes.
Another document dated early February raises doubts about the planned Ukrainian counteroffensive, warning of significant shortfalls in force generation and sustainment. The document also suggests that Ukraine's future counteroffensive may only result in modest territorial gains.
Defense Minister Oleksii Reznikov spoke about the intelligence leak during a visit to Spain on April 12, acknowledging that there is a "mix" of true and false information contained in them, with the former already being outdated.