The first two crashes occurred just after noon as a dust storm suddenly covered Interstate 10 near Picacho, about midway between Phoenix and Tucson. Those collisions involved 16 vehicles and led to the fatality.
Video showed dust roiling over dozens of cars, tractor-trailers and ambulances pulled over or strewn about the highway. Authorities were unable to transport injured motorists by helicopter because of the heavy dust.
One man was killed and at least 15 other people were injured in the accident, authorities said.Arizona Department of Public Safety officers and other emergency personnel make their way around vehicles involved in a crash on Interstate 10
The pile-ups involved a number of larger vehicles as well as cars
State public safety officers brave the dust storm to help in the massive clear-up operation
'It looked like a war zone,' Patrick Calhoun, one of the first rescuers to responder to the scene, told The Associated Press. 'This has been one of the worst pileups we've had on the I-10.'
Calhoun, with the Avra Valley Fire District, said the man who died was in the passenger seat of a car driven by his wife. Their car had slammed into the back of a semi and was lodged underneath it, killing the man almost instantly and leaving the woman critically injured in a semiconscious state of shock.
Calhoun said it took 45 minutes to hook up winches to the vehicle, pull it out and then cut the woman out of the car to take her to a hospital.
A second vehicle also was lodged under a semi, Calhoun said, and two people were extricated in a similar manner before being taken to a hospital.
A third pileup occurred almost two hours later on I-10 just north of Casa Grande and involved eight vehicles. No one was killed in that collision; two people had serious but non-life-threatening injuries, Graves said.
Katie Maass, a spokeswoman at University Medical Center in Tucson, said the hospital was treating 12 patients involved in the collisions. Three were listed as critical and the other nine were in serious condition as of Tuesday evening.
Authorities closed the interstate for most of the afternoon. They reopened the eastbound lanes around 5:45 p.m., and Graves said officials hoped to have westbound lanes reopened by 10 p.m.
Two other crashes later in the day likely were the result of dust, authorities said. A crash involving two tractor-trailers and a small car on I-10 near the Gila River Indian Community south of Phoenix seriously injured two people. Another crash on I-10 near Tonopah, west of Phoenix, didn't involve major injuries, authorities said.
Dust storms are common across Arizona during dry and windy conditions, and walls of dust more than a mile high can blanket an area in a matter of seconds, sometimes reducing visibility to zero.
Winds from the southwest were gusting at up to 40 mph throughout Arizona on Tuesday, said Jessica Nolte, a meteorologist with the National Weather Service in Phoenix.
"These winds have accumulated so much that when they move through the region they start to pick up the dry top soil," she said. "It can be a very rapid development."
The Phoenix area was enveloped in a beige haze for much of the day, obscuring the view of the mountains that surround the metropolitan area.
The winds should taper off Tuesday evening and into Wednesday, Nolte said. Another weather system was expected to move into Arizona on Thursday, and Nolte said it could generate gusts as strong as Tuesday's.
Nolte said the weather service did not issue a dust storm warning before it occurred but did warn people about the strong winds.
Although it was still early to evaluate the extent of Tuesday's damage, Graves said dust storms have created worse crashes.
One strong winter storm wreaked havoc in 2009 near Casa Grande, killing three people dead in a series of fiery crashes caused by thick, blowing dust on I-10. One of those killed was a man whose vehicle was rear-ended by his father's truck. Two teenage siblings also died.
'We did not have that, fortunately, in this situation,' Graves said. 'While it's sad there's a fatality and it's serious, it could have been a lot worse.'
