The FBI says it appears one of the bombs used in the attack at the Boston Marathon was housed in a pressure cooker hidden inside a backpack.
To maximize the impact of the shrapnel, the device may have included nails, BB's and ball bearings.
The FBI says the second bomb was also housed in a metal container, but there's not enough evidence to determine whether it was also in a pressure cooker.
Evidence recovered from the scene will be sent to the FBI's lab in Quantico, Virg., where analysts will reconstruct the devices used in the attack.
See images of the aftermath at the Boston Marathon after two devices exploded near the finish line.
Here's how some of the nation's newspapers covered the Boston Marathon blasts. Newspaper covers courtesy Newseum.
Despite all of the fear, anger and horror during the bombings at the Boston Marathon Monday, social media was abuzz showing off the heroism and bravery.
Police are currently out searching for a missing student from the University of Kansas.
The northwest side of the Kansas City Downtown Loop is back open after a serious accident…
Icy, snowy road conditions were to blame for several accidents around the metro.
One person is dead and two others injured following a two-car crash in Kansas City, Mo.