Conn. firefighters battle huge recycling plant blaze that could rage for days (PHOTOS, VIDEO)

People in Willimantic, Connecticut have been urged to stay indoors while fire crews battle a massive blaze at a recycling plant that officials say could take days to contain.

The fire broke out on Sunday morning before 10:30am local time at Willimantic Waste Paper Company. No one was inside the building at the time and no injuries have been reported.

Images from the scene show flames engulfing the building as plumes of thick black smoke billow into the air.

The heavy smoke was even detected on weather radar at 5,000 feet (1.5 km), according to local meteorologists.

At least 10 fire crews are at the scene, trying to bring the blaze under control, NECN reports. The building is full of waste and recycling materials, making the fire difficult to contain.

“We’re hunkering down for quite a long time here. I think we’re going to be on the scene here possibly for days,” Windham Town Manager Jim Rivers said.

Willimantic Police Department is urging people in the area to stay inside due to the poor air quality.

Department of Energy and Environmental Protection officials are also at the scene to monitor air quality and inspect the nearby Willimantic River for possible contaminants. It is not yet known what caused the fire