Authorities have closed a portion of Interstate 10 northwest of Tucson, Ariz., after a dust storm led to a multi-vehicle pileup.
Witnesses tell KVOA-TV in Tucson as many as 30 vehicles may be involved in the wreck near Picacho (pih-KAH'-cho).
There are reports of injuries, and several emergency crews are responding.
Authorities say visibility has been reduced to zero because of intense dust blowing in the area. The Arizona Department of Transportation reports the interstate is closed in both directions.