New York explosion: What we know – and don’t know

Updated 10:54 PM EDT, Sun September 18, 2016
Firefighters arrive at the scene of an apparent explosion in Manhattan's Chelsea neighborhood, in New York, Saturday, Sept. 17, 2016. A law enforcement official tells The Associated Press that an explosion in the Chelsea neighborhood appears to have come from a construction toolbox in front of a building. The official spoke on condition of anonymity because the person wasn't authorized to speak about an ongoing investigation. Police say 26 people have sustained minor injuries in the explosion on West 23rd Street. (AP Photo/Andres Kudacki)
Andres Kudacki/AP
Firefighters arrive at the scene of an apparent explosion in Manhattan's Chelsea neighborhood, in New York, Saturday, Sept. 17, 2016. A law enforcement official tells The Associated Press that an explosion in the Chelsea neighborhood appears to have come from a construction toolbox in front of a building. The official spoke on condition of anonymity because the person wasn't authorized to speak about an ongoing investigation. Police say 26 people have sustained minor injuries in the explosion on West 23rd Street. (AP Photo/Andres Kudacki)
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Story highlights

Mayor: Police are searching for suspects; the motive is unknown

Authorities are investigating whether a suspicious device found nearby is connected

(CNN) —  

An explosion in the heart of New York’s Chelsea neighborhood sent dozens to the hospital Saturday night. Shortly after the blast, investigators found a suspicious device a few blocks away, placing much of the city on edge.

Authorities know the bombing was intentional, violent and criminal, New York Mayor Bill de Blasio said.

But what we don’t know about the explosion, the mayor said, is just as important.

Here’s the latest, based on details authorities have revealed so far.

What happened in Chelsea?

01:40 - Source: CNN
Video shows explosion outside fitness center

What we know: Around 8:30 p.m. Saturday night, an explosion occurred at 23rd Street and 6th Avenue on Manhattan’s west side. A law enforcement source, speaking with CNN on the condition of anonymity, said the blast came from an explosive device planted near a dumpster. Shortly afterward, another suspicious device was found four blocks away on West 27th street: a pressure cooker with dark-colored wiring, according to law enforcement officials.

Surveillance footage of the explosion, including video from cameras at Orangetheory Fitness in Chelsea, captured bystanders running through the streets, ducking from debris as windows shattered all around.

What we don’t know: Why did the bomb go off in that location? Where did the explosive come from? And who was behind the blast?

How many people were hurt?

What we know: There were 29 victims injured in the explosion. Of those, 26 people were taken to a hospital. Armed guards stopped incoming vehicles to the hospital, including ambulances, to make sure none posed a threat to the medical facility.

By Sunday morning, all 26 patients had been released from hospitals.