Fire officials say a carelessly discarded cigarette started a warehouse fire in the eastern Phoenix suburb of Gilbert that generated thick black smoke that could be seen for miles.
Gilbert fire officials say someone threw a cigarette into an area of cardboard boxes, igniting a fire Monday afternoon in a backyard storage area behind Farnsworth Wholesale, a plumbing wholesale company.
Investigators are trying to determine if a company employee is to blame.
The blaze caused an estimated $8 million in damage. Farnsworth officials say the facility likely will be closed for several months.
Dozens of fire trucks from Gilbert, Tempe, Chandler and Mesa were at the scene and an aerial tanker sprayed water for about an hour.
State environmental officials allowed nearby residents to return by 7 p.m. Monday.
(Copyright 2012 by The Associated Press. All Rights Reserved.)