The Nevada Highway Patrol said the crash occurred at about 3 a.m. on Interstate 15 near Mesquite on the Arizona border, KLAS-TV, Las Vegas, reported.
Troopers said the driver of the SUV, a Dodge Durango, may have been drunk when the vehicle struck a Chevy Astrovan from the rear.
Five of the seven people in the Astrovan died in the crash. The other two, and two in the Durango suffered critical injuries.
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