FBI authorities are not commenting on the report as it still an ongoing investigation, said spokesman Andrew Ames.
Yonathan Melaku, 22, was arrested at Arlington National Cemetery on Friday after police feared he had bomb-making materials in a backpack he was carrying.
Police said he left his car parked in a wooded area behind the Pentagon and entered the cemetery.
His arrest sparked massive delays and headaches for commuters.
Forensic evidence has linked Melaku to shootings at various military installations, including the Pentagon and National Museum of the Marine Corps in Triangle.
