(CNN) -- At least three people died on a dust-covered stretch of highway Monday when at least 19 vehicles collided in a series of accidents because of poor visibility, a spokesman for the Arizona Department of Public Safety said.
Bart Graves said 12 other people were injured -- many of them seriously -- during the dust-storm-induced series of pileups that were flagged to CNN by Twitter.
Six tractor-trailers, one motor home and a dozen cars and trucks were involved in one of the wrecks on Interstate 10 near Picacho Peak. That included one semi with its nose smashed back to the windshield. Another trailer appeared to have a car wedged underneath.
A pickup truck lay on its side ahead of the main entanglement of crashed commercial trucks and cars.
At least two helicopter crews were summoned to deal with the injured, authorities said.
Westbound traffic bewteen mile posts 214 and 216 was being rerouted from the three-lane wide stretch to an adjacent side road. Other drivers were warned to avoid the area, because the highway will be closed for some time.