An electrical short is blamed for causing a fire that damaged a two-story home in Waterloo Thursday morning (April 6, 2017).

The blaze, at 1006 Riehl St., broke out around 7:30 a.m. Four people and a dog escaped the burning home through a side door. No one was injured, but a pet cat and five pet rats perished in the fire.

According to home owner Loren Swanson, the fire started near a portable heater on the enclosed front porch. He said the fire was sparked by an electrical short that was either in the heater cord or the outlet.

Swanson explained that he left the house to pick up some bagels at a nearby convenience store. When he returned, the television set wasn't working. Swanson then went to the basement and reset a thrown breaker in the circuit box. When the breaker tripped off a second time, Swanson said he started to unplug everything in the house.

It was then when Swanson noticed that thick, black smoke was filling the front porch and flames were climbing a wall. Battalion Chief Mike Moore of Waterloo Fire Rescue said the porch was fully engulfed when firefighters arrived a short time later.

Moore said the fire was contained to the front porch, which was heavily damaged. The rest of the structure sustained extensive heat and water damage.

The battalion chief confirmed that investigators believe an electrical problem caused the fire.