An early-morning fire on Tuesday destroyed five units in a south-side apartment building, displacing six residents.

The Tucson Fire Department responded to a call in the 300 block of West Irvington Road at 5:34 a.m., according to a news release.

The first firefighters on the scene reported heavy smoke and flames.

Firefighters evacuated residents and controlled the blaze in 12 minutes. Several people were treated at the scene for smoke inhalation, with one person taken to a hospital for evaluation, officials said.

A total of five apartments were condemned by city building-safety officials, and two vehicles parked near the building were damaged by the high temperatures.

The fire was caused by an electrical malfunction involving a refrigerator being plugged into an extension cord, officials said.