A fire damaged a duplex in downtown Charleston Thursday morning.

Charleston firefighters arrived at 708 Rutledge Ave. at 4:27 a.m. to see fire venting from the front and side of the two-story duplex, according to Ryan Kunitzer with the Fire Marshal Division.

The fire threatened nearby houses but was extinguished within 15 minutes, he said.

Damage was mostly contained to a second-floor utility room, with moderate damage to a bathroom and bedroom. First-floor units also sustained smoke and water damage.

The fire was reported when a barking dog woke up a man who lives on the first floor, Kunitzer said

Charleston and North Charleston firefighters responded to the blaze. No injuries were reported and the cause remains under investigation.