Corpus Christi Fire Fighters are investigating the cause of a fire at a vacant home in Annaville.

That blaze started Tuesday just after 8 at a home on Willow Wood Creek and Violet. Investigators say the fire started when a mattress on the back patio of the home caught fire --spreading to the home.

It took crews only 12-minutes to put out the flames. Investigators say the home was empty at the time of the fire because the home is for sale.