John Adams, left, Tommy DeStefano, center, and Dave Ellmer converse as they stand on a hill overlooking a large warehouse fire a day after flames engulfed the facility, Friday, Feb. 12, 2016, in Hillsborough, N.J. Firefighters have contained the massive fire and officials said the blaze didn't pose an imminent public health threat. Fire officials say plastic pellets were being stored in most of the complex, and environmental officials have been testing air quality. (AP Photo/Julio Cortez)
The Associated Press
HILLSBOROUGH, N.J. (AP) - Firefighters on Friday contained a massive warehouse fire that burned out of control for nearly 20 hours and generated so much smoke that it was detected by weather radar and forced some school closures.
The blaze did not pose an imminent public health threat, officials said. But schools were closed Friday in Hillsborough because of smoke from it.
The fire started Thursday afternoon at Veterans Industrial Park. Plastic pellets were being stored in most of the complex. Those pellets continued to burn even after officials contained the fire from spreading late Friday morning.
The complex once housed old military munitions and is near historic Duke Farms, the estate that belonged to late tobacco heiress Doris Duke.
The winter weather posed challenges to firefighters almost immediately, Hillsborough Fire Marshal Chris Weniger said. Strong winds fueled the blaze Thursday afternoon, and cold temperatures led to problems with freezing water.
Weniger said an outdated sprinkler system and aging fire hydrants on the property led to problems with water pressure for firefighters.
Firefighters also had to be rotated in and out of service. One suffered a minor leg injury.
Mayor Frank DelCore said there were some initial environmental concerns because a property adjacent to the fire was once a federal stockade for mercury, a highly toxic element.
However, the Republican mayor said the federal government had moved the mercury off the site several years ago. Nonetheless, state and federal environmental officials were on the scene to test air quality.
Fire trucks wait in line to fill up on water to battle a large warehouse fire a day after flames engulfed the facility, Friday, Feb. 12, 2016, in Hillsborough, N.J. Firefighters have contained the massive fire and officials said the blaze didn't pose an imminent public health threat. Fire officials say plastic pellets were being stored in most of the complex, and environmental officials have been testing air quality. (AP Photo/Julio Cortez)
The Associated Press
Smoke rises near a water tower at the site of a large warehouse fire a day after flames engulfed the facility, Friday, Feb. 12, 2016, in Hillsborough, N.J. Firefighters have contained the massive fire and officials said the blaze didn't pose an imminent public health threat. Fire officials say plastic pellets were being stored in most of the complex, and environmental officials have been testing air quality. (AP Photo/Julio Cortez)
The Associated Press
Smoke rises at the site of a large warehouse fire a day after flames engulfed the facility, Friday, Feb. 12, 2016, in Hillsborough, N.J. Firefighters have contained the massive fire and officials said the blaze didn't pose an imminent public health threat. Fire officials say plastic pellets were being stored in most of the complex, and environmental officials have been testing air quality. (AP Photo/Julio Cortez)
The Associated Press
Hillsborough Mayor Frank DelCore, front, speaks during a news conference in front of a large warehouse fire a day after flames engulfed the facility, Friday, Feb. 12, 2016, in Hillsborough, N.J. Firefighters have contained the massive fire and officials said the blaze didn't pose an imminent public health threat. Fire officials say plastic pellets were being stored in most of the complex, and environmental officials have been testing air quality. (AP Photo/Julio Cortez)
The Associated Press
Fire officials refill a fire truck with water to fight a large warehouse fire a day after flames engulfed the facility, Friday, Feb. 12, 2016, in Hillsborough, N.J. Firefighters have contained the massive fire and officials said the blaze didn't pose an imminent public health threat. Fire officials say plastic pellets were being stored in most of the complex, and environmental officials have been testing air quality. (AP Photo/Julio Cortez)
The Associated Press
Firefighters waiting to load load their truck with water look on as a news conference is held in front of smoke rising at the site of a large warehouse fire a day after flames engulfed the facility, Friday, Feb. 12, 2016, in Hillsborough, N.J. Firefighters have contained the massive fire and officials said the blaze didn't pose an imminent public health threat. Fire officials say plastic pellets were being stored in most of the complex, and environmental officials have been testing air quality. (AP Photo/Julio Cortez)
The Associated Press
A fire officials sprays water on a large warehouse fire a day after flames engulfed the facility, Friday, Feb. 12, 2016, in Hillsborough, N.J. Firefighters have contained the massive fire and officials said the blaze didn't pose an imminent public health threat. Fire officials say plastic pellets were being stored in most of the complex, and environmental officials have been testing air quality. (AP Photo/Julio Cortez)
The Associated Press
This photo provided by Nick Bowling shows a large fire at an industrial park in central New Jersey that closed down a major roadway and sent clouds of black smoke billowing into the sky. A stretch of Route 206 was closed in Hillsborough Thursday, Feb. 11, 2016, and smoke from the fire at Veterans Industrial Park can be seen for miles. No injuries have been reported, but witnesses say they've heard explosions that shook the ground and rattled windows. (Nick Bowling via AP)
The Associated Press
CORRECTS FROM N.C.TO N.J. -A person watches as smoke rise from a large fire at an industrial park Thursday, Feb. 11,2016, in Hillsborough, N.J. The fire in central New Jersey closed down a major roadway and sent clouds of black smoke billowing into the sky. (Ed Murray/NJ Advance Media via AP) TV OUT; MAGS OUT; INTERNET OUT; NO SALES; NO ARCHIVING; MANDATORY CREDIT
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