Joliet firefighters were at the scene of an Amazon warehouse fire for about five hours Monday.

A crew of firefighters remained on the scene overnight with the sprinkler system out of service to ensure there are no flare ups, the Joliet Fire Department said.

One firefighter was transported to the hospital for a shoulder injury.

The fire department responded at 3:28 p.m. to the warehouse at 4300 Brandon Road for a report of a structure fire, the fire department said.

Company 3 arrived to find the warehouse filled with smoke, and the sprinkler system was activated, the fire department said.

Firefighters located the fire deep inside the warehouse and it was beyond reach of the initial attack lines, the fire department said. Crews relocated to the south end of the building to make an interior attack on the fire.

Firefighters were challenged with zero viability, a heavy fire load, and material falling from the storage racks, the fire department said.

The sprinkler system helped keep the fire in check, so crews were able to work around the storage racks and begin attacking the fire, the fire department said.

The roof was opened over the fire to increase visibility. Roof crews saw fire above the sprinklers that the firefighters could not see from the floor, the fire department said.

After the main body of the fire was extinguished, crews worked aisle by aisle to remove product and extinguish any remaining spot fires, the fire department said.

Fire crews from stations 1, 3, 4, 6, 7 and 8 responded to the scene. The cause of the fire is under investigation.