CHARLOTTE, N.C. (WBTV) - A massive five-alarm fire broke out overnight at a self-storage unit building in Charlotte’s Steele Creek area.

Officials with the Charlotte Fire Department said the fire had been contained to one unit. By 7 a.m. Thursday, crews were still hard at work bringing the blaze under control.

Crews were first called to the Extra Space Storage building on South Tryon Street around 11:30 p.m. Wednesday. Video tweeted by the Charlotte Fire Department shows flames and heavy smoke pouring from the building.

Traffic Advisory; 10100 block of South Tryon St Outbound lanes are blocked due to fire department operations; seek an alternate routes. https://t.co/PndwipYbmW

A second alarm was struck at 11:48 p.m., according to CFD Capt. Jackie Gilmore. He said a third alarm was struck shortly after 12 a.m. Thursday, with Medic and Charlotte-Mecklenburg Police officers coming out to assist.

There were 90 firefighters on the scene as of 4:30 a.m., a five-alarm call, Gilmore said.

The captain said there were no injuries to firefighters, but they are tired.

According to Gilmore, the fire has been contained to one storage unit. The challenge for firefighters has been getting the fire contained, while simultaneously having to access locked units and move sometimes heavy materials, like furniture and appliances, that are inside.

#NOW The challenge? Getting the fire contained, while simultaneously having to access locked units, & move sometimes heavy materials (furniture, appliances, etc) inside. The captain says firefighters are okay but had to be pulled out a few times for safety checks. @WBTV_News https://t.co/TZgZ2ThEDX

Gilmore said firefighters are OK but had to be pulled out a few times for safety checks.

He asked drivers to cautious around the 10100 block of South Tryon Street, as crews continue to clear the scene.

The cause of the fire remains under investigation.

Check back with WBTV for updates as they come in.

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