PORT CHARLOTTE, Fla. - A massive fire at a storage building in Port Charlotte has sent five firefighters to the hospital.

At least a dozen firetrucks were helping to battle the fire at Storage America Self Storage off Sandhill Road.  Large flames could be seen, and heavy smoke damage is being reported to the building.

Charlotte County Fire says about 140 storage units are believed to be affected.  Customers with items stored there were asked not to come to the scene Monday night, but to check on their belongings on Tuesday.

The conditions of the hospitalized firefighters and nature of their injuries is not known.

The fire is burning near I-75, but authorities say no roads are closed.

The State Fire Marshall will be called in to investigate.