PASSAIC — A massive fire at a chemical plant in the city's downtown shut Route 21 in both directions on Friday night and resulted in evacuations from neighboring residences.

Residents of the city were being asked to stay away from the area, to stay indoors and to keep their windows closed.

Fire Chief Patrick Trentacost said the building was vacant when the fire broke out.

“A portion of the building did have chlorine in it and that seems to be under control at this time,” he said just after midnight. “We’ll be monitoring that also throughout the night but certainly we’re far from having control of the fire."

The message was amplified by Gov. Phil Murphy on Twitter.

"Praying for the safety of our first responders on the scene," Murphy said.

Mayor Hector Lora said about 9:30 p.m. that the eight-alarm fire had not yet impacted the chemicals at the warehouse on Passaic Street. The fire was at the Qualco chemical plant, which produces pool-treating chemicals, and gaming and hotel furniture manufacturer Majestic Industries. 

The mayor said the fire was still contained to the warehouse but the flames were getting perilously close to the chemical storage, resulting in officials calling on neighbors to evacuate their buildings. The fire, however, did eventually spread to multiple buildings.

The Department of Environmental Protection was on scene assessing air quality, Lora said.

Firefighters from neighboring cities were responding to the blaze in Passaic.

Police also blocked streets for several blocks to allow firefighters access to hydrants.

Towering flames were visible from the nearby highway before it was closed and a colossal plume of smoke was visible for miles in the night sky.

New York City Emergency Management sent a notification Friday night saying residents might see or smell smoke from the fire.

The cause of the fire remained under investigation.

Injuries had not been reported as of 10 p.m. but officials expected the structure to be destroyed.

This is a breaking news story and will be updated as more information is confirmed.

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