U.S. & World

NEW YORK (CBS) ― A small bomb caused minor damage to an empty military recruiting station in Times Square early Thursday, shaking guests in hotel rooms high above "the crossroads of the world."

Police blocked off the area to investigate the explosion, which occurred at about 3:45 a.m. No one was injured. The blast left a gaping hole in the front window and shattered a glass door, twisting and blackening its metal frame.

Authorities said at a news conference that a witness saw a person on a bicycle wearing a backpack and acting suspiciously, but that no one saw a person place the device in front of the recruiting center.

"Whoever the coward was that committed this disgraceful act on our city will be found and prosecuted to the full extent of the law," Mayor Michael Bloomberg said. "We will not tolerate such attacks."

"If it is something that's directed toward American troops than it's something that's taken very seriously and is pretty unfortunate," said Army Capt. Charlie Jaquillard, who is the commander of Army recruiting in Manhattan.

He said no one was inside the station, where the Marines, Air Force and Navy also recruit.

"The fact that this appears deliberately directed at the recruiting station insults every one of brave men and women in uniform stationed around the world," Bloomberg said.

New York Police Commissioner Ray Kelly says the device was a "low order" explosive device, apparently made out of a green ammunition crate.

An intense manhunt was underway for the perpetrator. Kelly said a witness at the scene saw a man wearing a hood, dark colored clothing and carrying a backpack on the island where the blast occurred. The man was riding a bicycle.

Subway trains were prevented from stopping at the Times Square station during the initial investigation, but police later allowed subway traffic to resume.

Witnesses staying at a Marriott hotel four blocks away said they could feel the building shake with the blast.

"I was up on the 44th floor and I could feel it. It was a big bang," said Darla Peck, 25, of Portland, Oregon.

"It shook the building. I thought it could have been thunder, but I looked down and there was a massive plume of smoke so I knew it was an explosion," said Terry Leighton, 48, of London, who was staying on the 21st floor of the Marriot.

Members of the police department's bomb squad and fire officials gathered outside the station in the early morning darkness, and police cars and yellow tape blocked drivers - most of them behind the wheels of taxicabs - from entering one of the world's busiest crossroads. Police began allowing some traffic through around the start of rush hour.

The recruiting station, located on a traffic island surrounded by Broadway theaters and chain restaurants, has occasionally been the site of anti-war demonstrations, ranging from silent vigils to loud rallies.

In October 2005 a group of activists who call themselves the Granny Peace Brigade rallied there against the Iraq war. Eighteen activists, most of them grandmothers with several in their 80s and 90s, were later acquitted of disorderly conduct.

The recruiting station was renovated in 1999 to better fit into the flashy ambiance of Times Square, using neon tubing to give the glass and steel office a patriotic American flag motif. For a half century, the station was the armed forces' busiest recruiting center. It has set national records for enlistment, averaging about 10,000 volunteers a year. 

Sources tell CBS station WCBS-TV in New York City, the blast may have been related to two other minor explosions in the city.

In October, two small explosive devices were tossed over a fence at the Mexican consulate, shattering three windows but causing no injuries. No threats had been made against the consulate, and no one took responsibility for the explosion, police said.

At the time, police said they were investigating whether it was connected to a similar incident at the British consulate on May 5, 2005.

In that incident, the explosions took place in the early morning hours, when Britons were going to the polls in an election that returned Prime Minister Tony Blair to power.

In both cases, the instruments were fake grenades sometimes sold as novelty items. They were packed with black power and detonated with fuses, but incapable of causing serious harm, police said.

Police have released footage from a private security camera showing a cyclist riding up to the Times Square military recruiting station where a small bomb was detonated.

The bicyclist is seen getting off the 10-speed bike at 3:40 a.m. Thursday, and the blast occurring three minutes later. It is followed by a brief flash and a cloud of white smoke.

Police say they later found the bike in the trash.

Police Commissioner Raymond Kelly said the device, though
"unsophisticated," could have caused "injury and even death."

(© 2009 CBS Broadcasting Inc. All Rights Reserved. This material may not be published, broadcast, rewritten, or redistributed. The Associated Press contributed to this report.)