Investigators have determined the explosion which started a fire in a mobile home park was caused by an uncapped customer gas line.
Authorities responded to the scene near MC 85 and Litchfield Road around 8:30 a.m. Saturday. Firefighters said the explosion came from one mobile home, and the fire spread to two others nearby.
Two people were sent to the hospital in critical condition and several others were treated for smoke inhalation.
Authorities said the two seriously hurt remained in critical condition as of Sunday afternoon, preventing investigators from interviewing them to learn more about what happened leading up to the explosion.
Southwest Gas, which provides service in Avondale, said it was working with police and fire on the investigation. Utility officials said it's the customer's responsibility to make sure all unused lines are capped. Uncapped lines, or lines with a break, will give off the rotten egg smell and the gas will blow dust and leaves away should there be a hole in the cap or line.
The Red Cross responded to the scene and was helping nine people displaced as a result of the explosion and fire.