FBI launches terrorism investigation after homemade explosive device ignited outside of NYC Mayor Mamdani’s residence

The device ignited outside the New York City mayor’s residence on Saturday contained explosive materials and fragmentation that could have killed and maimed numerous people, according to law enforcement sources familiar with the investigation. A federal terrorism investigation is underway and terrorism charges are pending.

Two people from Pennsylvania were arrested outside Gracie Mansion, which is the home of Mayor Zohran Mamdani and his wife, on Saturday afternoon, after a suspicious device was ignited.

NYPD Commissioner Jessica Tisch told reporters on Saturday that an anti-Islam protest was organized by people associated with Jake Lang, a pardoned Jan. 6 rioter and far-right influencer. A group of counter-protesters, numbering more than 100, also gathered, and two young men from Pennsylvania, angered by the anti-Islam protest, brought the homemade bombs to the gathering, intending to cause harm, law enforcement sources told CBS News.

The NYPD’s Bomb Squad sent the devices to the FBI’s Quantico lab for analysis. One of the devices was determined not to be a “hoax device or a smoke bomb,” but instead it was “an improvised explosive device (IED) that could have caused serious injury or death,” Tisch said in a statement Sunday.

Law enforcement sources told CBS News that the devices consisted of a sports drink bottle filled or partially filled with explosive material set inside glass jars and surrounded by fragmentation, or nuts and bolts. The fuse was apparently connected to an M80-type firework.

Two sources told CBS News that the IEDs contained triacetone triperoxide, or TATP, a volatile explosive material. It is often synthesized from acetone and hydrogen peroxide, appearing as a white crystalline powder. 

Another suspicious device was found Sunday in a vehicle on East End Ave. about three blocks south of the park where Gracie Mansion is located, the NYPD said, prompting “limited evacuations of buildings in the vicinity while the Bomb Squad assesses and removes the device.”

The FBI’s Joint Terrorism Task Force has taken the lead and launched a terrorism investigation. Search warrants were expected to be executed in Pennsylvania and New Jersey, sources told CBS News.

Videos showing the chaos from the protests, verified by the CBS News Confirmed team, show a man apparently yelling “Allahu Akbar” – or “God is Most Great” – just as a protester, identified as 18-year-old Emir Balat, of Pennsylvania, allegedly throws an “ignited device.”

Investigators are looking to determine if at least one of the subjects was inspired by ISIS extremist messaging, sources told CBS News.

Tisch described the device as “a jar wrapped in tape, importantly with nuts, bolts and screws along with a hobby fuse.”

According to Tisch, the first device thrown by Balat extinguished itself after striking a barrier in a crosswalk, a few feet from police officers.

Balat then ran away and allegedly retrieved a second device from 19-year-old Ibrahim Kayumi, lit the device and started running with it before dropping the device, Tisch said. 

Balat and Kayumi, also from Pennsylvania, were taken into custody. Police arrested a person, identified as 21-year-old Ian McGuiness, who allegedly used pepper spray on counter-protesters, and three others on disorderly conduct and obstruction charges.

Investigators are looking into the overseas travel for Balat and Kayumi. Balat left the U.S. for several months and traveled to Istanbul from May 6 to Aug. 26, 2025. Meanwhile, Kayumi traveled to Istanbul for several weeks in July and August 2024 and to Saudi Arabia in late March of that year. 

In a statement on Sunday, Mamdani specifically mentioned Lang and said the protest outside Gracie Mansion was “rooted in bigotry and racism” and has no place in New York City.

“It is an affront to our city’s values and the unity that defines who we are,” he said.

He did not name the two men who were arrested for the IEDs. Instead, he said, “The attempt to use an explosive device and hurt others is not only criminal, it is reprehensible and the antithesis of who we are.”