An explosive device damaged a military recruiting station in New York City's Times Square early Thursday.

FBI investigating and seeking any information.

Other U. S. recruiting stations put on alert.

Police say someone threw the device at the recruiting station several hours before dawn. The blast shattered a large portion of the building's front window, but no injuries were reported.

Police and fire crews cordoned off Times Square and diverted underground subway trains for several hours, but normal traffic resumed by the start of the morning rush hour.

People in hotels hundreds of meters away said they heard the explosion. Police are investigating a report that someone riding a bicycle may have thrown the small bomb at the recruiting station.

The recruiting station is on a small traffic island in the center of Times Square, surrounded by theaters, restaurants and retail stores. Most were closed at the time of the explosion. Times Square, which marks the intersection of Broadway and Seventh Avenue, is one of the city's busiest crossroads.