FLAGSTAFF, Ariz. -- Authorities say four people are dead after two vehicles collided head-on Interstate 40 about 15 miles east of Flagstaff.
Arizona Department of Transportation officials say three other people were taken to Flagstaff hospitals for treatment after the crash late Thursday morning.
The names of the dead and injured weren't immediately released.
ADOT spokesman Raul Garcia says one vehicle crossed over the median for an unknown reason and struck the other car head-on.
Authorities say both lanes of I-40 were closed for several hours after the crash, resulting in a 10-mile traffic backup.
Eastbound lanes reopened around 12:30 p.m. Eastbound was reopened shortly before 2 p.m.
The KTAR Newsroom contributed to this report.