Ahmad Khan Rahimi

In April 2017, the defense team filed a motion for a change of venue, requesting that the trial be held in Burlington, Vermont. They argued that the extensive pre-trial publicity in New York would prevent their client from getting a fair trial in Manhattan. The court denied this motion the following month.

On October 16, 2017, after a two-week jury trial, Rahimi was found guilty of all eight charges in federal court in New York. The mandatory sentence is life without parole. Rahimi was removed from the courtroom during opening statements after making repeated outbursts. During the trial, the government introduced into evidence Rahimi's fingerprints and DNA on unexploded bombs and bomb debris; videotape of Rahimi pulling the luggage containing the bombs; and testimony from detectives, computer analysts, and others. The government also presented as evidence a journal carried by Rahimi at the time of his arrest that read: "Everything had to be done quietly and I had to lie to cover my tracks. The sounds of the bombs will be heard in the streets. Gun shots to your police. Death to your oppression." The government also presented evidence from Rahimi's Internet bookmarks, which included bomb-making guides that appeared in al-Qaeda propaganda. A juror interviewed following the verdict called the evidence of guilt overwhelming. Officials also stated that he tried to convert other jailers to extremist ideologies before and during the trial. On February 13, 2018, Rahimi was sentenced to life in prison without parole.

On September 19, 2016, the sole suspect—Ahmad Khan Rahimi, of Elizabeth—was captured, following a shootout with police in neighboring Linden, New Jersey. 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 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 sentence of life without parole.

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.

In July 2016, Rahimi passed the required background check and legally purchased the Glock 9 mm handgun he used in the subsequent shootout, from a licensed dealer in Salem, Virginia.

In June 2016, Rahimi's wife left the United States, planning to return September 21. On September 19, following her husband's arrest, she was stopped by the United Arab Emirates authorities. Two days later, she returned to New York and was questioned by the investigators. The wife was cooperative and not accused of wrongdoing.

The explosion disrupted travel in Manhattan extensively. A significant zone (14th Street to 34th Street between Fifth Avenue and Eighth Avenue) was closed to car travel overnight. By 7:00 a.m. the following morning, all roads in that region were reopened except for West 23rd Street. New York City Subway service to stations along West 23rd Street was disrupted while the investigation was ongoing.

Both of the Manhattan bombs—the one that exploded and the second that was disabled—were of the same design, using pressure cookers filled with bearings or metal BBs that were rigged with flip phones and Christmas lights that set off a small charge of hexamethylene triperoxide diamine (HMTD), which served as a detonator for a larger charge of a secondary explosive similar to Tannerite.

Rahimi's friends described him as a generous person who was never devoutly religious and would invite his friends to eat and conduct rap battles at his family's fried chicken restaurant—First American Fried Chicken in Elizabeth, 15 miles (24 km) from New York City. To some, he was known as Mad, short for Ahmad. A classmate from Edison High described him as quiet, mild-mannered, well-dressed, and "not abrasive, [but] funny" whenever he spoke. In recent years, though, he seemed to be a "completely different person" who was more stern than before and less easygoing. Also, in elementary school, Ahmad's teacher complained to Mohammad that his son was "act[ing] like a king in class". Ahmad broke a friend's nose while in junior high.

At one time, Rahimi was licensed to carry firearms. In August 2014, he, at that time living in Perth Amboy, New Jersey, was charged with aggravated assault and unlawful possession of a weapon in Union County. The charges arose from allegations that Rahimi had stabbed his brother in the leg, after the victim and another brother attempted to stop Rahimi from assaulting their mother and sister "for no apparent reason". Rahimi was reported by two of his siblings the next day and spent three months in the Union County Jail, but was reported to have bailed. A grand jury declined to make an indictment, and the charges were dropped on September 22.

Rahimi's father Mohammad had tried to contact the FBI about his son around August 2014, but two months later, Rahimi was cleared by the FBI. One reason cited was that Mohammad had stated that he was merely angry over the August domestic incident when he reported his son, so he had denied his previous statement. In an interview with The New York Times, Mohammad claimed that he had seen his son watching videos made by al-Qaeda and the Taliban and asked him to stop. However, the FBI later said Mohammad never informed them of what he had seen.

On September 20 — the day after his arrest — Rahimi's estranged ex-girlfriend, and the mother of his daughter, filed a petition in a New Jersey state court seeking full custody of the child, citing Rahimi as being a possible participant in "terrorist related activity" in New York City. She also filed to change her child's name, as well as to force the media not to contact her or her daughter. The petition for custody was granted the following day, though the request to change the daughter's name was denied, as was the request for media not to contact her, because "the court said it had no authority to grant the requests." Rahimi and the mother of his child had engaged in a long-running battle, as Rahimi owed her more than $3,000 in child support in 2015; she had previously gotten a restraining order against Rahimi.

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.

In Kuchlak, Rahimi attended an Afghan-run Naqshbandi religious seminary closely associated with the Taliban movement, where he took lectures in Islamic education for three weeks. Rahimi remained in Pakistan from April 2013 to March 2014, and traveled to Afghanistan during the period. Following his near-year-long stay in the region, he underwent additional screening. On both occasions, he stated that he visited family members and was cleared by immigration and customs officials. The FBI did not find any signs of ties to terrorism during background checks.

In a statement, the Council on American–Islamic Relations welcomed the arrest of Rahimi, saying, "American Muslims, like all Americans, reject extremism and violence, and seek a safe and secure nation. Our nation is most secure when we remain united and reject the fear-mongering and guilt by association often utilized following such attacks."

A "high-ranking law enforcement official with knowledge of the investigation" said Rahimi had spent two additional days in jail, one in February 2012 for allegedly violating a restraining order, and another in October 2008 for failure to pay traffic tickets.

Rahimi, reportedly, went back to Afghanistan several times (including for an extended period starting in 2012), and "showed signs of radicalization" afterwards. The trips were reportedly arranged by Rahimi's pious father, who was concerned about his son being "too Americanized". Rahimi and members of his family also made several trips to Pakistan, where they had Afghan relatives living as refugees. According to a family friend, Rahimi claimed that his father took away his passport while he was sleeping and left him alone in a foreign country.

The Rahimi family had a history of disputes with the City of Elizabeth over their restaurant's operating hours, claiming that the city was discriminating against them because of their ethnicity and because they were Muslim. They filed a lawsuit against the city in 2011, in which they alleged harassment and religious discrimination by police and officials who would force them to close early. Mayor J. Christian Bollwage said the longstanding issues were caused by a series of complaints from neighbors, who reported noise and large crowds gathering at the restaurant late at night. The city later barred all takeout restaurants, including the Rahimis', from operating past 10:00 p.m. In 2009, two of Rahimi's brothers were arrested for attempting to record a conversation with police, according to court papers. Rahimi lived above the restaurant with his family.

Rahimi and a brother spent several weeks in the Pakistani cities of Quetta and nearby Kuchlak, as well as Kandahar, Afghanistan. At Quetta, which is home to a large population of Afghan immigrants and some Taliban members-in-exile, he was in an arranged marriage with a Pakistani woman, believed to be his cousin, in July 2011, and had a son with her in 2014. The son's fate is unknown. Rahimi also went under the wing of a local radical cleric, according to a close relative in Afghanistan. Following Rahimi's arrest, a spokesman for the Afghan Taliban said the group had no connection with him.

A note found on the pressure cooker bomb left on West 27th Street referred to Anwar al-Awlaki (the Muslim cleric who became a senior member of al-Qaeda and was then killed by a U.S. drone strike), the Boston Marathon bombing, and the 2009 Fort Hood shooting.

Rahimi graduated from Edison High School in 2008. From 2010 to 2012, he attended Middlesex County College in Edison, New Jersey, majoring in criminal justice with alleged aspirations of a future in law enforcement. He dropped out.

While at Edison High, he started a relationship with a classmate from the Dominican Republic, which culminated in them having a daughter together in 2007, during Rahimi's senior year. According to people close to the Rahimis, this upset Mohammad Rahimi, who refused to meet his granddaughter or the mother, and had been disapproving of the relationship due to expectations that his son would marry a cousin in Afghanistan. In March 2008, after returning from his first trip in Pakistan, he moved in with his girlfriend's family and got a job at a Kmart store. Rahimi's girlfriend later ended the relationship and sued him for child support. This reportedly depressed Rahimi, who subsequently returned to his family, and damaged his relationship with his father.

Ahmad Khan Rahimi (born January 23, 1988), an Afghan American whose surname was initially reported as Rahami, came to the United States from Afghanistan in 1995, and was naturalized in 2011. He is a native Pashto speaker.

Following the explosion, officers began a block-by-block search for additional unexploded bombs. Several hours later, police received a 9-1-1 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. When authorities came to look, two state troopers discovered the pressure cooker bomb concealed in a plastic bag and connected with dark wiring to a mobile phone. The bomb was filled with small bearings or metal BBs. The pressure cooker bomb was described as similar to those used in the Boston Marathon bombing. The New York City Police Department (NYPD) reported its find of a "possible secondary device" at 11:00 p.m.

The FBI examined fingerprints from the undetonated West 27th Street pressure cooker bomb and its attached mobile phone. DNA evidence was also recovered. On September 19, the FBI traced the prints, as well as some pictures on the mobile phone, to Ahmad Khan Rahimi (see below).

According to a childhood friend, Rahimi grew a beard, started wearing more religious clothing following his trips to Afghanistan, and began praying in the back of his family's restaurant. When the mobile phone from West 27th Street was examined, investigators found that Rahimi had posted jihadist writings on various websites. In addition, his handwritten journal was found, expressing a desire to become a martyr. However, it was "not known whether he had any links to an overseas terror organization, or whether he had been inspired by such organizations and their propaganda efforts, as others have been." One intelligence source said Rahimi may have been self-radicalized.

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, many restaurants, and a Trader Joe's at 21st Street and 6th Avenue. The Chelsea neighborhood is residential, known for its nightlife, and is not close to any significant tourist sites or government buildings.

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.

Investigators discovered surveillance video that showed a suspect planting a bomb, later identified as Rahimi, on West 23rd Street in Manhattan, then walking to West 27th Street dragging a duffel bag. The subject left the bag at West 27th Street. Later, two individuals took the pressure cooker bomb out of the bag and left the scene. Authorities determined that the two men who had taken the bomb out of the bag were, most likely, scavengers who had only wanted the duffel bag and did not know what they had been handling; in the process, they might have deactivated the bomb in the bag. The NYPD and FBI wished to talk with these men, who were considered possible witnesses but were not suspected in helping plant the bomb. Investigators later believed the men were possible Egyptian tourists who have since returned to their home country. U.S. investigators notified Egyptian authorities that they wanted to question the men.