PASSAIC, N.J. (1010 WINS) -- A massive chemical fire broke out at a warehouse in downtown Passaic Friday night, with smoke so heavy that it was detected on weather radar in New York City.

The fire at the Majestic Industries warehouse and Qualco chemical plant broke out at 8:30 p.m. Friday, sending a huge plume of smoke into the air that could be seen for miles.

"There have been bad fires but this is the worst that I've ever seen," Passaic Mayor Hector Lora said Friday night.
The fire happened in buildings holding plastics, pallets and chlorine, officials said, and at its worst reached 11 alarms.
Fire Chief Patrick Trentacost said the part of the area where most of the chlorine was under control. Many areas of the building collapsed, causing falling debris to be another concern for fire officials, according to NJ.com. Lora said around 8 a.m. Saturday that the situation was "contained."

Lora said if the fire had gotten to the main plant, where hundreds of thousands of pounds of chlorine were stored, it likely would have caused evacuations and been an even greater disaster.
Firefighters remained at the scene Saturday morning, where the fire was still being dealt with, but was down to four alarms.
Nearby residents were not required to evacuate, with Lora saying an air quality assessment from the state deemed to situation to be “acceptable,” but residents were told to close their windows.

Security guard Justin Johnson told WCBS-TV he was the only one in the building, checking water pressure, when he noticed smoke coming from a smokestack-like tower. He wasn’t sure what to make of it but called the fire department as alarms went off.
Water from firefighter hoses froze in cold weather and made the environment slick and hazardous for responders.
One firefighter was taken to a hospital after being struck by debris, officials said. He was doing well, though other firefighters slipped and fell in the slick conditions, officials said.

The Associated Press contributed to this report.