'AN INTENTIONAL ACT': Dozens injured in New York City explosion

• An explosion in the Chelsea neighborhood of New York City went off around 8:30 p.m. ET Saturday night.

• At least 29 people were injured. All have been released from hospitals.

• A second possible device resembling a pressure cooker was found four blocks from the scene of the explosion and removed around 2:25 a.m. ET Sunday morning by the NYPD's bomb squad.

• NYC Mayor Bill de Blasio called the explosion "an intentional act." New York Gov. Andrew Cuomo referred to it as an "act of terrorism."

• Currently, police have no evidence of a connection to an international terror group.

An explosion left 29 people injured in New York City on Saturday night in what New York City Mayor Bill de Blasio called an "intentional act," while police in Manhattan also removed a second device resembling a pressure cooker later in the night.

New York Gov. Andrew Cuomo said the incident is being investigated as an "act of terrorism," though he said there were no known connections to international terror groups.

According to the New York City Police Department, the initial explosion occurred in the Chelsea neighborhood on 23rd Street between 6th and 7th Avenues around 8:30 p.m. ET.

Photos from the scene:

The New York City Fire Department said there were 29 injuries. By Sunday morning, Cuomo said all 29 had been treated and released from hospitals, though he said the explosion had left the area with significant damage.

In a press conference Saturday night, de Blasio said there was no specific and credible threat against New York City. He called the explosion "an intentional act." Cuomo said that while there was no current connection to international terror groups, the incident would be investigated as an act of terror.

"A bomb exploding in New York is obviously an act of terrorism, but it's not linked to international terrorism," he said.

Police have no suspects but are reviewing security footage as well as civilian video.

"We are still in the process of trying to figure that out," police commissioner James O'Neill said at a press conference, according to The New York Times.

The White House said late Saturday night that President Barack Obama had been briefed about the explosion.

Here's video apparently showing the explosion:

A possible second device resembling a pressure cooker was reportedly located at 27th Street between 6th and 7th Avenues, according to the NYPD. The NYPD bomb squad removed the device at 2:25 a.m. ET and took it to the department's firing range in the Bronx to be inspected by robots, The Times reported.

The police department urged people in that area to "stay away from windows facing 27th Street" until the "suspicious package" was cleared.

Cuomo said both devices in New York City were similar in design.

The explosion occurred on the same day that a pipe bomb exploded near the site of a charity event in New Jersey. That incident occurred shortly before thousands of runners were due to participate in a charity 5K race to benefit US Marines and sailors, authorities said. New York City officials say the two incidents do not appear to be related.

Cuomo said evidence from both sites would be sent to the FBI's lab in Quantico, Virginia.

This is the site of the explosion and the location of the second possible device:

Business Insider reporter Michelle Mark captured some video and images from the scene:

The NYPD's counterterrorism unit tweeted this image from the area:

Christina Sterbenz contributed to this report.