Chattanooga firefighters were called to a fire at an apartment complex on McBrien Road Thursday evening.

It happened at Royal Arms Apartments in the 300 block, shortly before 5:00 p.m.

Officials say a porch on one of the units was on fire when firefighters arrived at the scene. The flames eventually climbed up an outside wall and into the attic of the unit.

A dozen fire companies responded to the scene. Some of the firefighters attacked the flames, while others worked quickly to make sure all residents in the complex were evacuated.

Firefighters had the blaze under control in less than 30 minutes.

The cause of the fire is unknown and under investigation.

No one was injured.

The damage estimate is unknown at this time.

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