A fire broke out at a recycling center in Port Morris early Thursday morning.

News 12 is told employees called 911 around midnight to respond to the recycling plant on Walnut Avenue and 136th Street.

The FDNY says it took crews about three hours to completely put out the fire due to the heavy smoke.

The chief tells News 12 at one point crews had to regroup because they couldn't pinpoint where the fire set off, due to the thickness of the smoke. He says they also had to call for backup.

About 100 firefighters worked to extinguish the flames

The FDNY says five firefighters suffered minor injuries and are expected to make a full recovery.

News 12 is told the three employees inside at the time of the fire made it out safely.

The exact cause of the fire is under investigation.