The two men, 18 and 19 years old respectively, are suspected of attempting to carry out an "IS-inspired" act, New York police chief Jessica Tisch announced at a press conference.
On Saturday, a far-right figure gathered for a demonstration against Islam outside Gracie Mansion, the New York mayor's residence. A larger group of counter-protesters also gathered there.
During the gatherings, a man threw a device that began to smolder and emit smoke. According to media reports, it was an explosive device intended to kill.
The two men were arrested and two more homemade explosive devices were later found in the area. No one was injured.
