Explosive Residue Found in Storage Unit Linked to ISIS-Inspired NYC Attack: FBI

The FBI found explosive residue in a Pennsylvania storage unit linked to an ISIS-inspired attack by two men accused of attempting to detonate improvised explosive devices (IED) outside the New York City mayor’s home, the agency said on March 10.

After their arrests this past weekend, the two suspects, 18-year-old Emir Balat and 19-year-old Ibrahim Kayumi, told law enforcement that they were inspired by the terrorist group, law enforcement and a criminal complaint said.

“I pledge my allegiance to the Islamic State,” Balat told officers, adding that he wanted to carry out an attack bigger than the 2013 Boston Marathon bombing that killed three people and injured more than 500.

When asked by a bystander about his motivation, Kayumi responded “ISIS,” court documents show.

New York Gov. Kathy Hochul said on March 9 that the state will remain in a “heightened threat environment.”

The suspects’ federal charges include attempting to provide material support to a foreign terrorist organization, carrying a maximum sentence of 20 years, and using a weapon of mass destruction, carrying a maximum sentence of life in prison.

They are held without bail and have not yet entered a plea.

FBI bomb technicians conducted controlled detonations of the explosive residue overnight on March 9. The storage unit is in Langhorne, Pennsylvania, which is near where Balat’s family resides, according to the agency.

Local police said on March 10 that the controlled detonations resulted in “several loud bangs.”

The men drove from Philadelphia, where they live, to New York City on March 7 to carry out the attack with homemade bombs near Mayor Zhoran Mamdani’s residence, Gracie Mansion, in Manhattan, officials said.

Mamdani called Balat and Kayumi’s attack a “heinous act of terrorism” as they proclaimed “allegiance to ISIS,” he wrote in a March 9 post on X.

“They should be held fully accountable for their actions,” the mayor said. “We will not tolerate terrorism or violence in our city.”

White House press secretary Karoline Leavitt on March 10 described the attack as “absolutely despicable.”

Balat is a senior at a high school in Langhorne, but a spokesperson for his school said he had not attended classes since enrolling in a virtual program in September 2025.

Kayumi is from Newtown, Pennsylvania, which is only about four miles from Langhorne. He graduated from his high school in 2024, a school spokesperson said. Kayumi’s mother filed a missing persons report on the day of the attack, claiming that she hadn’t seen her son since that morning, court documents show.

While Balat’s attorney, Mehdi Essmidi, said his client had “complicated stuff going on,” Kayumi’s attorney, Michael Arthus, declined to speak to reporters after a court hearing on March 9.

Officials said the two suspects joined a group of about 125 counterprotesters on March 7 outside Mamdani’s mansion to confront about 20 people protesting what they called an Islamic “takeover” of the city.

Jan. 6, 2021, rioter Jake Lang organized the protest, dubbed the “Stop the Islamic Takeover of New York City.” Mamdani is the first Muslim mayor of New York City.

Tensions escalated after a protester with Lang’s group used pepper spray against the counterprotester group.

Balat then was seen on video surveillance hurling an IED, filled with nuts, bolts, and screws, with a lit fuse toward protesters and police, but the device extinguished itself before it could hurt anyone or cause any damage. The man dropped a second device near law enforcement officers and ran, but he was ultimately caught and arrested, according to the criminal complaint.

Bomb technicians determined that the devices were capable of serious injury or death.

In total, six individuals, including Balat and Kayumi, were arrested in connection with the March 7 attack. The individual who used pepper spray was also arrested.

The Epoch Times requested comment from both men’s attorneys regarding the FBI finding explosive residue as part of their investigation, but neither responded by publication time.

New York Police Commissioner Jessica Tisch said on March 9 that the attack is being investigated as an act of ISIS-inspired terrorism.

The city remains on heightened alert.

A park near the mayor’s residence was evacuated and several nearby streets closed on the afternoon of March 10 as police investigated reports of a “suspicious device.”

“The NYPD responded immediately and secured the area,” Mamdani wrote in a post on X.

Officials later said the device was nonthreatening.

The Associated Press contributed to this report.