A device thrown by a counterprotester at an anti-Islam demonstration in New York City on Saturday was confirmed to be an improvised explosive, according to a preliminary police analysis. As the investigation continued on Sunday, police said they were looking into a second suspicious device found in the same area of Manhattan’s Upper East Side.

Two people were in custody for their alleged role in Saturday’s confrontation, which unfolded during a “Stop the Islamic Takeover of New York City” event led by the far right activist Jake Lang outside the Manhattan residence of Mayor Zohran Mamdani.

The sparsely attended event drew a far larger group of counterdemonstrators, including one person who tossed a smoking object containing nuts, bolts, screws and a “hobby fuse” into the crowd, police said.