Surveillance Video Shows Moment of New York City Explosion At least 29 people were injured in the blast in the Chelsea neighborhood.

 -- Surveillance video captured the shocking moment an explosion rocked New York City's Chelsea neighborhood Saturday night, injuring at least 29 people.

The "large explosion" on 23rd Street between Sixth and Seventh Avenues was seen by police officers driving by around 8:30 p.m., according to police. The fire department also heard the explosion and responded immediately.

In the video, after the blast hits, debris flies through the air and pedestrians run and scatter on the sidewalk.

Mayor Bill de Blasio said the blast appears to have been "an intentional act" but with no apparent link to terrorism. Law enforcement is investigating the cause of the explosion, authorities said.

None of the 29 injured appears to have been seriously hurt.