The investigation involves drones, helicopters and a review of everyone who called 911 about the blazes, he said. "We're going to get to the bottom of what happened," he said, adding that investigators should have an answer to whether there was a "nefarious origin" in the coming days.

Gov. Kathy Hochul declared a state of emergency and said state agencies were responding to the fires around the Pine Barrens, a wooded area that is home to commuter towns east of New York City. She said homes, a chemical factory and an Amazon warehouse were at risk and more evacuations may be needed.

Two commercial buildings were damaged and two firefighters suffered minor injuries, Suffolk County Fire Coordinator Rudy Sunderman said.