STERLING, Va. — Federal authorities say they have arrested a Virginia man and charged him with attempting to obstruct a terrorism investigation.

The Washington Post reports that according to records filed in federal court, Sean Andrew Duncan, of Sterling, Virginia, owned a phone that revealed research into materials relating to the Islamic State, terrorist attacks, weapons, surveillance tactics and body armor.

Duncan was arrested Friday on charges that he allegedly destroyed a thumb drive that authorities say may have contained evidence of criminal activity.

Federal investigators first became aware of Duncan’s activities in February 2016 after a relative reported to the FBI that he had converted to Islam and had possibly become radicalized.

It was not immediately known if Duncan has an attorney.

Sterling is 35 miles (56 kilometers) northwest of Alexandria.