
A still image from video footage courtesy WPXI-TV shows stabbing suspect Alex Hribal dressed in a hospital gown after his arraignment with Sheriff’s deputies in Export, Pennsylvania April 9, 2014. REUTERS/WPXI-TV
A still image from video footage courtesy WPXI-TV shows stabbing suspect Alex Hribal dressed in a hospital gown after his arraignment with Sheriff’s deputies in Export, Pennsylvania April 9, 2014. REUTERS/WPXI-TV
A woman walks onto the campus of the Franklin Regional School District where several people were stabbed at Franklin Regional High School on Wednesday, April 9, 2014, in Murrysville, Pa., near Pittsburgh. The suspect, a male student, was taken into custody and being questioned. (AP Photo/Gene J. Puskar)
The building where the mass shooting happened. (Ahmad Ali Karim for Ahmad Ali JetPlane Pics).
Boston Marathon bomb scene pictures taken by investigators show the remains of an explosive device. REUTERS
Boston Marathon bomb scene pictures taken by investigators show the remains of an explosive device. REUTERS
Boston Marathon bomb scene pictures taken by investigators show the remains of an explosive device. REUTERS
Boston Marathon bomb scene pictures taken by investigators show the remains of an explosive device. REUTERS
Boston Marathon bomb scene pictures taken by investigators show the remains of an explosive device. REUTERS
Boston Marathon bomb scene pictures taken by investigators show the remains of an explosive device. REUTERS
Boston Marathon bomb scene pictures taken by investigators show the remains of an explosive device. REUTERS
This image from a Federal Bureau of Investigation and Department of Homeland Security joint bulletin issued to law enforcement and obtained by The Associated Press, shows the remains of a pressure cooker that the FBI says was part of one of the bombs that exploded during the Boston Marathon. The FBI says it has evidence that indicates one of the bombs was contained in a pressure cooker with nails and ball bearings, and it was hidden in a backpack. (AP Photo/FBI)
This image from a Federal Bureau of Investigation and Department of Homeland Security joint bulletin issued to law enforcement and obtained by The Associated Press, shows the remains of a black backpack that the FBI says contained one of the bombs that exploded during the Boston Marathon. The FBI says it has evidence that indicates one of the bombs that exploded in the Boston Marathon was contained in a pressure cooker with nails and ball bearings, and it was hidden in a backpack. (AP Photo/FBI)