Harker Heights (FOX 44) — Harker Heights firefighters are looking for the cause of a building fire that damaged a four-plex in the 200 block of Oak Trails Drive.

Firefighters went to the building around 4:20 p.m. Friday afternoon. They found heavy smoke and fire pouring out of the ‘A’ unit, but had it out in 15 minutes.

The flames did significant damage to that unit, according to firefighters. The other three units have minor smoke damage.

One person went to the hospital because of the fire. That person’s condition is unknown at this time. A Harker Heights firefighter was treated for a minor injury.

A pet dog did not make it out of the residence and died in the fire.

At least six people had to leave their homes because firefighters had to cut the power to the entire building. The fire department says those people found places to stay and did not need Red Cross assistance.