BOSTON: A 21-year-old US national guardsman was charged with leaking a trove of classified United States government documents as he made his first appearance in court Friday.

Jack Teixeira was arrested Thursday following a week-long probe into one of the most damaging leaks of secrets since the 2013 dump of National Security Agency documents by Edward Snowden.

He was charged with the “unauthorized retention and transmission of national defense information” at a short hearing in Boston.

He is also accused of the “unauthorized removal and retention of classified documents or material.”