'Loud, long boom': Bomb blast in Manhattan injures 29

Bomb-blast site in Chelsea section of New York

At least 29 people were injured in an apparent bomb blast on 29th Street between 6th and 7th Avenues in Manhattan Saturday night, with Mayor Bill De Blasio insisting there is currently no evidence of a terror plot.

Police officers, firefighters and other first responders rushed to the blast scene, which closed a major roadway, forced people out of nearby buildings and brought onlookers to the area.

New York Mayor Bill de Blasio said in the initial hours after the explosion, authorities had found "no evidence at this point of a terror connection to this incident."

De Blasio said that the explosion was "an intentional act," but during a briefing late Saturday, he said little other information was available because the investigation was in its early stages.

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"The exact nature and cause of this explosion has not yet been determined," James O’Neill, the New York police commissioner marking his first day in the position, said at the news conference late Saturday. O’Neill did say that natural gas had been ruled out as a possible cause.

The New York Police Department's counterterrorism bureau said it was responding to the explosion, which came hours after a pipe bomb exploded in a Jersey Shore garbage can shortly before a scheduled charity race there benefiting Marines and Navy sailors.

De Blasio said authorities had not found anything connecting the Chelsea and New Jersey incidents. He also said that there was no specific, credible threat against New York from any terror group.

While O’Neill said authorities were still trying to determine what, precisely, exploded, the New York Police Department's counterterrorism bureau posted a photo online earlier Saturday showing what appeared to be a dumpster or garbage container mangled by a blast.

Container mangled by bomb blast

The FBI said it was involved in the response and the Bureau of Alcohol, Tobacco, Firearms and Explosives said its arson and explosives task force was being dispatched to the explosion scene.

Police in New York also reported shortly after 11 p.m. that they had found "a possible secondary device" a few blocks away from the explosion scene.

Officers were directing people away from this other intersection, and one could be heard telling pedestrians that "there is a possible explosive" in the area.

The White House also issued a statement regarding the explosion.

"The president has been apprised of the explosion in New York City, the cause of which remains under investigation. The president will be updated as additional information becomes available."

Earlier in the day, another bomb exploded in Seaside Park, New Jersey.

A Marine charity race was scheduled to begin early Saturday, but was delayed.

Moments before it was to start, a pipe bomb hidden in a trash can exploded.

The boardwalk and beach area were quickly evacuated when police discovered more bombs wired together had failed to detonate.

Runners in the charity race had been scheduled to pass by the area at the time of the blast, but the event had coincidentally been delayed. No injuries were reported.

A four-block perimeter around the site was quickly evacuated, and residents were ordered to stay indoors as authorities swept the area for any more devices. Route 35 was shut down, and no incoming traffic was permitted into Seaside Park for much of the day; only outbound traffic was permitted.

The race was a Semper Five event for U.S. Marines. The explosion occurred at 9:35 a.m., five minutes after the race had been scheduled to begin. The site of the blast was about three-quarters of a mile from the initial starting line.

A shorter "fun run" event for youth runners had also just ended when the blast occurred.

Al Della Fave, the county prosecutor's office spokesman, says it is too soon to know whether the bomb was placed with terrorist motives. But he agreed that the incident appears to have targeted U.S. military members and their families, due to the timing and nature of the detonation.

A photo of the garbage can where the blast occurred snapped by witness Chad Ruedin shows that the bottom of the can had been completely blown off. Ruedin says he was a couple blocks away from the blast site, and assumed the cannon-like sound was to signal the start of the 5K race when he heard it. He says he walked over and snapped the photo of the garbage can as police began to arrive.

The prosecutor's office spokesman says the race had been delayed due to strong turnout and last-minute registrations, possibly saving lives by preventing the race from beginning on time.

About 3,000 people, including 1,600 runners, had been in the area at the time for the event, which is intended to support U.S. military service members.

The Semper Five 5K race was canceled following the explosion.

The FBI and Department of Homeland Security are leading the investigation. Anyone with information on the incident is urged to call 1-800-CALL-FBI and select Option No. 1.

Evacuated residents were allowed to return to their homes with proper identification as of 6 p.m. Saturday, but authorities say that some ocean beaches in the area of D Street and Ocean Avenue will remain closed until further notice.