Fire officials say it's becoming a common event in Casper, fires started by people improperly disposing of smoking materials.

Casper Fire-EMS was called out to a structure fire in the 1100 block of South Nebraska Street about 11:00 Friday morning. According to a release, when crews arrived they found a small fire burning on an exterior wall on the back side of a multi-unit apartment building. The fire was extending into wall space but had not yet burned into the interior of the apartment.

The only occupant of the residence at the time of the fire noticed smoke inside, called 911 and evacuated. Firefighters used a portable pressurized water extinguisher to put out the fire. The fire caused minimal damage and occupants were able to return home immediately. There were no injuries reported.

Fire investigators determined the cause was accidental, the result of improperly discarded smoking materials on an exterior deck which ignited combustible materials of the structure. They say the wind may also have been a factor.

Fire officials say exterior fires caused by discarded smoking materials are becoming a common event in Casper, and wind is almost always a factor in the ignition and acceleration of these types of fires.

Here's more from Casper Fire-EMS:

"We would like to remind Casper residents to use caution when smoking indoors or out. Assure complete extinguishment of smoking materials before discarding, especially in outdoor structures such as decks and patios. Thoroughly extinguish, ideally by immersing in water. Discard in a metal container such as bucket covered with a tight lid. Never discard by leaving them exposed in open ash trays or uncovered receptacles. Also, never discard them in potted plants as organic materials in the pot can ignite easily."