Edmonton Fire Rescue said a blaze that damaged two garages in the city’s west end earlier in the week was caused by oil-soaked paper towels that ignited on a back porch.

Firefighters were called to the home in the area of 145 Street and 88 Avenue just before 11 p.m. Monday and they arrived to find fire burning in the detached garage,

The fire spread to a neighbouring garage.

Water used to put out the blaze caused minor flooding in the basement. The fire was under control more than a half hour later, and out just before 1:45 a.m.

At first, investigators could only confirm the blaze started on the back deck of a home.

On Friday, officials confirmed the fire started when paper towels soaked with some type of cooking oil (used to wipe down a hot griddle) ignited inside a cardboard box left on the deck.

EFRS spokesperson Maya Filipovic said organic oils, such as vegetable-based cooking oils, can self-heat and can start fires when left on fabric or other material. Fabric used to wipe up organic oils should be washed and hung up to dry.

Damage has been pegged at $175,000 for the home, garage and contents where the fire started, and damage to the structure and contents of the second garage are estimated to be $35,000.