NEW YORK (WNBC/Jonathan Dienst and Ida Siegal) — Some 29 people were injured in an explosion in Chelsea Saturday night, and authorities are investigating a possible secondary device a few blocks away.
"All hands are on deck; injuries are significant," Mayor Bill de Blasio told a news conference.
"There is no evidence at this point of a terror connection," he said, though he added it was "an intentional act."
President Obama was briefed on the explosion and receiving regular updates.
Crews responded to the scene at 23rd Street and Sixth Avenue around 8:30 p.m. A law enforcement source said the explosion appeared to have come from a large construction-site toolbox on 23rd.
Just after 11 p.m. ET, NYPD Special Operations tweeted that they were investigating a possible secondary device on 27th St. Preliminary indications from a senior official were that a pressure cooker was found sitting out in the open.
Huge explosion in Chelsea blew this dumpster ... pic.twitter.com/1lSIGjRyC8— Chris Duffy (@voicehalf) September 18, 2016
Photos posted to social media showed an extensive emergency presence at the scene, with the area between Sixth and Seventh avenues cordoned off. Sixth Avenue was closed from 14th to 34th Street and NYC Transit reported extensive disruptions to the 1, 2, E and F subway lines.
At least one Twitter user tweeted that her "whole high-rise building shook" from a apparent blast. Another image showed a Dumpster or trash bin blown apart, with bits of debris scattered on the sidewalk. People at least seven blocks away reported hearing and feeling a loud boom.
Earlier Saturday, one of three bundled pipe bombs placed in a trash can along a 5k race route to be run by Marines detonated in Seaside Park, New Jersey. The race had been running late, but authorities said they believed the device had been timed to explode as runners went by the trash bin.
No one was hurt, and de Blasio said there was no evidence of a connection between the two blasts.
Read the full story at NBCNewYork.com.
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