Jack Teixeira, a member of the intelligence wing of the Massachusetts Air National Guard, has been arrested by the Federal Bureau of Investigation in connection to a series of leaked classified United States government and military documents.

According to VOA, 21-year-old Teixeira was arrested Thursday afternoon at his residence in Dighton, Massachusetts.

U.S. attorney general Merrick Garland said in a statement that Mr Teixeira was arrested “in connection with an investigation of alleged unauthorised removal, retention and transmission of” classified national defence information. 

“This investigation is ongoing. We will share more information at the appropriate time,” said Mr Garland.

Mr Teixeira allegedly leaked classified documents, including highly sensitive information about Ukraine’s military capabilities and the U.S. intelligence community’s reach into Russia’s military command.

After the information, which sent shockwaves across the Pentagon, became public, the U.S. government admitted the country has some members of its special forces stationed at the American Embassy in war-torn Ukraine. But they refused to say the exact number of military personnel.

Charging documents have not been filed yet against Mr Teixeira. But he is expected to make his first appearance in federal court in Boston on Friday.