The man is believed to be a naturalized U.S citizen from Ethiopia.
FBI Special Agent Brenda Heck described the man as being “approximately in his twenties” and said he was “not forthcoming” when he was arrested.
Law enforcement work near the Pentagon after a suspicious vehicle forced multiple road closures Friday.
The car was searched by bomb experts, Heck said, who did not find “significant explosive related materials.”
Agents also found a backpack near the vehicle containing “suspicious items” that Heck said were a “non-explosive unknown material.”
The FBI said the suspect, 22-year-old Lance Cpl. Yonathan Melaku, is a naturalized citizen who was born in Ethiopia. He joined the Marine Corps Reserves in September 2007, is listed as a motor vehicle operator with the 4th Combat Engineer Battalion, headquartered in Baltimore, and has not been deployed overseas. He has received the National Defense Service Medal and the Selected Marine Corps Reserve Medal.