Firefighters were battling a large blaze early Saturday morning at a chemical plant in Passaic, N.J., that had erupted the night before, sending towering flames into the sky and clouds of smoke wafting through the region.
No major injuries were reported, the city’s mayor said, but the fire was still raging.
“We’re going to be fighting this fire for days,” the mayor, Hector C. Lora, said in a brief telephone interview before dawn.
Mr. Lora had urged residents on Friday night to stay away from the area to allow firefighters from around the region to battle the 11-alarm blaze at the plant, which houses a company, Qualco, that manufactures chlorine for swimming pools. Mr. Lora said he was also asking residents to shut their windows to keep out the smoke.
In an earlier telephone interview on Friday night, Mr. Lora said that about 100,000 pounds of chlorine in the plant had been “impacted” by the fire, the heat from the flames or water from the firefighters’ hoses.
As a result, he said, a Reverse 911 call went out to residents in the city and in Bergen County, advising them to keep their windows shut. He said, however, that the part of the plant where most of the chlorine was stored had not been affected.
“We are not at a place where we believe the danger or the threat would justify evacuations,” Mr. Lora said, adding that if there were toxic fumes, the firefighters “would have been pulled from the site.”
Mr. Lora said in the later interview, shortly after 4 a.m., that environmental officials were monitoring air quality in the area and that no evacuation orders had been issued. Mr. Lora himself was still at the scene, speaking from a car parked near the chemical plant.
Patrick Trentacost Sr., the Passaic fire chief, said about 11 p.m. Friday that the chlorine that had burned was “nothing to be concerned about at this time.”
“But we are monitoring it constantly,” he said. “We have companies in the chemical factory, and we are watching very closely where this fire is going.”
Mr. Lora estimated on Friday night that more than 200 firefighters from the region had responded to the fire, which began just after 8:30 p.m. He said on Saturday morning that a number of them had been sent home.
One firefighter had sustained a minor eye injury, and there had been a few “slips and falls,” he said. But there had been no major injuries.
Mr. Lora said on Friday that he had spoken to Gov. Philip D. Murphy, who dispatched state environmental and emergency management officials to the scene.
“We won’t be able to fully inspect until fire is completely put out,” Mr. Lora wrote on Facebook. “It may take some time to establish cause. Main issue with chlorine fire is wind.”
Mr. Murphy said on Twitter that he was urging “everyone in Passaic to stay safe,” and he asked those near the fire to keep their windows closed.
“Praying for the safety of our first responders on the scene,” Mr. Murphy wrote.
Video posted on social media showed a large ball of flame erupting along the side of a highway as thick clouds of smoke roared into the sky. The flames drew crowds of onlookers, some of whom reported hearing explosions and seeing sparks.
New York City officials said that residents there might see or smell smoke from the fire in Passaic, a city of about 70,000 residents, which is about 10 miles from Manhattan.