The New York Police Department stepped up security at hotels, landmarks like the World Trade Center site, Times Square and other locations Monday following explosions at the Boston Marathon.
Critical response teams, which are highly visible patrol units that travel in packs with lights and sirens, are being deployed throughout the city until more about the explosion is learned, chief police spokesman Paul Browne said.
More than 1,000 counterterrorism officers were mobilized, along with the thousands of other officers on patrol. Highly trafficked areas like Times Square, Rockefeller Center and St. Patrick's Cathedral in Midtown Manhattan, the United Nations, and the World Trade Center site were being especially monitored, police said.
Security was also beefed up within the subways. The Metropolitan Transportation Authority said it was also stepping up patrols on the Long Island Rail Road and Metro North commuter rails. Browne said those actions are being taken as precautions.
"We don't have intelligence at this point to indicate that this is a prelude, but we take precautions as if it were, so that we would be in a position to intercept anything coming our way."
Mayor Michael Bloomberg said the department was fully prepared to protect the city.
"Some of the security steps we are taking may be noticeable," Bloomberg said. "And others will not be."
The blasts occurred at the finish line of the marathon. The explosions have killed two people and injured at least 23 others. The cause wasn't known.
The NYPD regularly steps up security in the city as a precaution based on incidents in other locations.
With additional reporting by Annmarie Fertoli