Suspect a Former Marine Corps Reservist ARLINGTON, Va. - UPDATE: FOX News has confirmed that the man taken into custody early Friday after being found near the Pentagon with suspicious materials in his backpack is former Marine Corps reservist Yonathan Melaku. 22-year-old Melaku was arrested in Arlington Cemetery overnight. He was believed to have a backpack containing 5 lbs of a substance that was labeled ammonium nitrate. Tests showed the material to be an "inert" substance. A notebook was also found in his bag with words such as Taliban and Al Qaeda. Melaku was a Lance Corporal Marine corps reservist...