Police in New York are investigating a serious security incident after an explosive device was thrown during protests outside the official residence of Mayor Zohran Mamdani.

The incident happened outside Gracie Mansion on Manhattan’s Upper East Side, where a small anti-Islam protest had gathered. The demonstration quickly turned tense as a much larger group of counter-protesters arrived at the scene.

According to the NYPD, one person lit and threw what investigators later confirmed was an improvised explosive device into the protest area. Officials said the device contained materials such as nuts and bolts and could have caused serious injury or death.

The device struck a barrier near police officers and went out before detonating. A second suspicious device was also discovered nearby and is now part of the investigation.

Authorities arrested two suspects at the scene and several others were taken into custody during the clashes between protesters and counter-protesters. Federal investigators, including the FBI’s Joint Terrorism Task Force, are now assisting in the case.

Mayor Mamdani strongly condemned the violence and said hate and intimidation have no place in New York City. Police confirmed that the mayor and his family were not harmed during the incident.

The investigation is ongoing as officials work to determine exactly how the devices were made and whether additional charges will be filed.