At approximately 8:30 p.m. Sat., September 17, an explosive device detonated inside a dumpster in New York’s Chelsea neighborhood at 23rd Street and 6th Avenue. Police counterterrorism officers, a bomb squad, and firefighters rushed to the scene.

New York City Mayor Bill de Blasio told reporters early indications are the explosion “was an intentional act.” Mayor de Blasio went on to say there is no evidence this explosion was terroristic in nature.

Witnesses described a loud, strong bang that shook buildings in the area and blew out windows.

New York City Police Commissioner James O’Neill, who took over as commissioner on September 16, told CNN reporters, “The exact nature and cause of this explosion has not yet been determined.”

Police presence has increased across New York City.

The New York Police Department Bomb Squad was searching the area, checking garbage cans, for any other possible explosive devices.

The NYPD Special Operations Division tweeted at around 11 p.m. that a “possible secondary device” was located at 27th Street.

An eyewitness to the event told ABC news, “[I] felt a loud explosion and I felt like a lightning bolt struck the building. It, like, shook the ground. Everybody ran out of the restaurant into the street. The whole city was in the street.”

The force of the explosion was so great windows shattered and caused significant enough damage to necessitate the closing of portions of the subway.

Despite the chaos, Mayor de Blasio said New York will remain strong. “Whatever the cause, whatever the intention here, New Yorkers will not be intimidated,” de Blasio said in an interview.

This explosion comes just hours after another explosion in New Jersey at a charity run. As with the Chelsea explosion, there were no fatalities. The charity race, the Seaside Semper Five, raises money for members of the United States Marine Corps and their families.