Gracie Mansion Bomb Attack Was ISIS-Inspired, Officials Say

UPPER EAST SIDE, NY — The handmade bombs thrown during dueling protests Saturday outside Gracie Mansion were confirmed Monday to be "ISIS-inspired" attacks, New York City Police Department Commissioner Jessica Tisch said Monday.

According to Tisch, both suspects — Emir Balat, 18, and Ibrahim Kayumi, 19 — will be prosecuted in Manhattan federal court and official charges will be filed later on Monday.

"After that complaint is made public, which I expect to occur later today, I will be able to say much more about the investigation and what we have learned in this case, but it is crucial that we respect that process and not get ahead of it," Tisch said outside of Gracie Mansion during a press conference. "That being said, I can confirm this morning that this is being investigated as an act of ISIS-inspired terrorism."

The chaotic scene first unfolded when tensions escalated between protesters and counter-protesters outside of Gracie Mansion on the Upper East Side around noon on Saturday, Mayor Zohran Mamdani said at Monday's press conference. Mamdani lives at Gracie Mansion with his wife, Rama Duwaji. Gracie Mansion is located at 181 East End Ave. near East 88th Street.

The initial protest was an anti-Islam protest led by conservative influencer Jake Lang that drew about 20 people, and a counterprotest that drew roughly 125 people to East End Avenue and 87th Street, Tisch said.

First, a device was thrown toward the protestors, but the device hit a police barricade and extinguished itself. Tisch described the explosive as a jar wrapped in black tape with nuts, bolts and screws, and a hobby fuse that could be lit, about the size of a football.

When the first suspect, Balat, took off running, Kayumi handed him a second device, which Balat lit and dropped between 87th and 86th streets, Tisch has said. Both were chased and apprehended at the scene, Tisch said.

In connection with the ongoing investigation, New York police said on Sunday that they identified a third explosive device in a vehicle on East End Avenue between 81st and 82nd streets, which was removed after civilians were evacuated from the area.

Tisch said that both suspects traveled from Pennsylvania to New York.

"Preliminary test results determined that these were not hoax devices, nor smoke bombs. They were improvised explosive devices that could have caused serious injury or death," Tisch said. "Part of our initial investigation was to determine what energetic substance, if any, was used in the two devices, and our analysis showed that one of the devices deployed by the subjects contained the substance triacetone triperoxide, known as TATP."

The New York City Police Department is working on the case with the U.S. Attorney’s Office for the Southern District of New York and the FBI.

"Let me say this plainly: anyone who comes to New York City to bring violence to our streets will be held accountable in accordance with the law. As this case continues to develop, I will remain in close contact and communication with our police commissioner," Mamdani said.

This is a developing story and will be updated. For questions and tips, email Miranda.Levingston@Patch.com.