Pentagon Shooter Pleads Guilty An ex-Marine who caused a terror scare at the Pentagon and Arlington National Cemetery last summer pled guilty Thursday to firing shots at military buildings in the Washington, D.C. area. Yonathan Melaku, then 22, was arrested on June 17, 2011 after he was seen in Arlington National Cemetery at night with a backpack. The backpack allegedly contained a package labeled ammonium nitrate, a common fertilizer than can be used in explosives, spent firearm ammunition and a notebook referencing the Taliban, Osama Bin Laden and al Qaeda. After his arrest, FBI agents searched his Virginia home and found a list of bombmaking components as well as a video of Melaku shouting "Allahu Akbar" as he fired his gun at the National Museum of the Marine Corps in October 2010. The shots did $90,000 worth of damage to the museum windows. On the video Melaku states, "That's a military building and that's the building I'm going to be targeting. .. . Last time I hit them, they turned off the lights for like ... four or five days.... Punks! Now, here we go again. This time, I'm gonna turn it off permanently. Alright. Alright, next time I turn on this video, I'm gonna be shooting them. That's what they get... . That's the target. That's the military building that's going to, gonna get attacked. According to an FBI affidavit, the items on the alleged bombmaking list were "consistent with the requirements for a time power unit and firing mechanism of an improvised explosive device (IED). Those items, combined with Ammonium Nitrate, would in fact make up several significant components required for the manufacture of an IED. Agents also conducted a review of Melaku's computer and found "numerous documents concerning bomb-making and explosives," according to the affidavit in the case. Melaku pled guilty to firing at the Pentagon, the museum and two military recruiting centers and agreed to a 25-year sentence. Melaku, an Ethiopian native, is a naturalized U.S. citizen and joined the U.S. Marine Reserves in 2007 where he has risen to the rank of Lance Corporal in the Combat Engineer Support Company, according to the FBI. He has never been deployed abroad, but was awarded the National Defense Service Medal and the Selected Marine Corps Reserve Medal. The military shootings began Oct. 17, 2010 at the Marine Corps Museum, when someone fired at least 10 bullets at the building. Two days later, six or seven shots were fired at the Pentagon, and bullets became embedded in the building's blast-proof windows. On Oct. 26, shots were fired at a Marine Corps recruiting center in Chantilly, Va. The shooter struck a second time at the Marine Corps museum on Oct. 29, then hit a Coast Guard recruiting station in early November.