Three people are dead after a dust storm caused multiple crashes on Interstate 10 between Phoenix and Tucson on Tuesday.
The Arizona Department of Public Safety says up to six commercial vehicles may have been involved in the chain-reaction.
DPS officials say several passenger cars were also involved. One was sandwiched between two 18-wheelers. Some medical helicopters were taking some of the 12 people injured to hospitals.
DPS officials say the crashes closed westbound lanes of I-10 North of Picacho Peak.