Flames spread quickly through pounds of waste paper and plastic in a Fox Point recycling center, sending about 75 firefighters out Wednesday evening.
Firefighters responded to a fire at the Recycling Management Resources Wilmington location around 6 p.m. and called for backup when they found heavy, black smoke pouring out of the warehouse.
Tom Finocchiaro, Fire Chief at Brandywine Hundred, said the 100 Amer Road warehouse was full of smoke. The fire started at a machine used to sort the paper and plastic, but the paper rapidly caught on fire and stayed smoldering.
Crews used a loader to remove the ignited paper and plastic outside to extinguish, while others battled the smoke and flames inside.
"We had to minimize what was burning in the building," he said.
One of the concerns was the lack of fire hydrants at the warehouse, Finocchiaro said. All the water used was brought in with tankers and engines carrying up to 4,000 gallons of water.
Firefighters from Delaware County, Pennsylvania assisted in putting out the flames.
The cause of the fire is still being investigated by the state fire marshal's office, Finocchiaro said.
Employees were working at the time of the fire, but there were no reported injuries.