New York, NY -- Police in New York are still trying to determine exactly what kind of device a bomber used to blow a gaping hole in the front window of an empty military recruiting station in Times Square.
Police say they found a found a metal ammunition box that is believed to have contained the explosive, and it is being sent for testing. Police also say the box is readily available in Army-Navy surplus stores.
Investigators released surveillance video from the scene in hopes it will shed light on the bombers identity.
The early morning blast also shattered a glass door. No one was hurt.
Police say a witness saw a person on a bicycle wearing a backpack and a hood and acting suspiciously, but no one saw the device being placed in front of the recruiting center.
A Pentagon spokesperson says military offices across the country went on higher alert to guard against attacks.