Story highlights Eastbound highway traffic was shut down for four hours after the crash

A tractor-trailer was heading west on I-10 when it crossed the divide

It struck a van going the opposition way, killing all 7 van passengers, a state official says

The truck's passengers are both in serious condition at a Phoenix hospital, he adds

A tractor-trailer crossed the median of an Arizona highway Sunday and slammed into a van driving in the other direction, killing all seven of the van's passengers, a state public safety spokesman said.

The two people in the truck -- the driver and his spouse -- were both injured in the crash and helicoptered to Banner Good Samaritan Hospital in Phoenix, said Officer Carrick R. Cook with the Arizona Department of Public Safety.

The woman has a broken back, and she and her husband are both in serious condition, according to the spokesman.

The truck had been heading west on Interstate 10, about 40 miles west of Phoenix, about 11 a.m. when it went across the highway and struck the van, which was going east.

Both vehicles went off the right side of the highway after the collision and caught fire, Cook said.

Medical examiners are trying to determine the identities of the seven van passengers killed, she added. They are believed to be from western Arizona.

The crash caused massive traffic issues, as authorities shut down Interstate 10 eastbound before noon and funneled drivers off the highway. One lane was reopened about 4:30 p.m., according to the state Department of Transportation's official Twitter feed.

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