Ahmad Khan Rahimi

In the Chelsea neighborhood of Manhattan in New York City, on the same day as the Seaside Park bombing, a pressure cooker bomb filled with shrapnel, in the form of small bearings or metal BBs, exploded in a crowded area on West 23rd Street, between Avenue of the Americas and Seventh Avenue at 8:31 p.m. The explosion occurred in front of 133 West 23rd Street in the vicinity of a construction site, at which materials were in place for exterior renovations of the Visions at Selis Manor facility, an apartment building for the blind, at 135 West 23rd Street.

Other nearby buildings included the Townhouse Inn of Chelsea, and many restaurants.

The Chelsea neighborhood is primarily residential, and has an active nightlife scene.

Witnesses said that the explosion "seemed to have started inside a sidewalk dumpster" in the vicinity of Sixth Avenue, and photographs of a "twisted dumpster" in the middle of West 23rd Street went viral on Twitter.

A law enforcement official speaking on condition of anonymity stated that the explosion "appeared to have come from a construction toolbox" in front of a building, and photographs of the area reportedly showed a twisted, crumpled black metal box.

The explosion "was powerful enough to vault a heavy steel dumpster more than 120 feet through the air ... Windows shattered 400 feet from where the explosion went off, and pieces of the bomb were recovered 650 feet away."

The explosion caused damage to a nearby five-story brownstone, and debris was strewn in front of the St. Vincent de Paul Church.

The moment of the blast was captured on closed-circuit television footage from three cameras.

Thirty-one people were injured, 24 of whom were taken to four hospitals.

Most injuries were scrapes and bruises caused by flying debris and glass.

None of the injuries were ultimately life-threatening, but one victim sustained penetrating trauma to the abdomen and was rushed from the scene in serious condition.

Nine of the injured were taken to Bellevue Hospital, including the seriously injured person.

Lenox Health Greenwich Village treated another nine victims.

By the following morning, all of the injured had been released.

The explosion disrupted travel in Manhattan extensively.

New York City Subway service to stations along West 23rd Street was disrupted while the investigation was ongoing.

Following the explosion, officers began a block-by-block search for additional unexploded bombs.

Several hours later, police received a call from a resident of West 27th Street who had seen a suspicious-looking package near her home.

The device was under a mailbox at West 27th Street between Sixth and Seventh Avenues, four blocks away from the site of the original blast.

Two state troopers arrived and discovered the pressure cooker bomb concealed in a plastic bag and connected with dark wiring to a mobile phone.

By 7:00 a.m. the following morning, all roads in the neighborhood were reopened except for West 23rd Street.

A significant zone (14th Street to 34th Street between Fifth Avenue and Eighth Avenue) was closed to car travel overnight.

On September 17–19, 2016, three bombs exploded and several unexploded ones were found in the New York metropolitan area.

The bombings left 31 people wounded, but no fatalities or life-threatening injuries were reported.

On the morning of September 17, a pipe bomb exploded in Seaside Park, New Jersey.

Later that day, a homemade pressure cooker bomb went off in the Chelsea neighborhood of Manhattan, New York City.

A second pressure cooker bomb was discovered four blocks away.

Late on September 18, multiple bombs were discovered at the train station in Elizabeth, New Jersey.

One of these bombs detonated early the next day.

On September 19, 2016, the sole suspect—Ahmad Khan Rahimi, of Elizabeth—was captured, following a shootout with police in neighboring Linden, New Jersey, which left two officers injured.

Rahimi was not part of a terrorist group, but his actions were believed to have been influenced by the extremist Islamic ideology espoused by al-Qaeda.

In the morning of September 17, 2016, in Ocean County, New Jersey, the Seaside Semper Five, a 5K run event, was expected to draw as many as 3,000 people, with many of them being veterans of the United States Armed Forces.

The race was delayed after a suspicious backpack was noticed in the vicinity of the starting point.

At about 9:30 a.m., shortly before the race was supposed to start, a pipe bomb exploded in a trash can on Ocean Avenue in Seaside Park.

Three "rudimentary" pipe bombs, all reportedly timed to go off during the race, were later found, with only one of the three having exploded.

No one was hurt by this bombing, however.

The race was canceled after the explosion, and the beach and boardwalk in Seaside Park were evacuated.

Police officials and federal agents soon went door-to-door, asking residents about information regarding the bombs or any suspicious activity they may have seen, heard, or witnessed.

In 2017, Rahimi was convicted in U.S. federal court of eight federal crimes arising from the attack.

On February 13, 2018, Rahimi was sentenced to a mandatory term of life without parole.