A sports utility vehicle went airborne and struck an embankment on a highway Friday, killing all seven people inside. Police said the driver may have fallen asleep.

Police said the accident occurred on Interstate 40 around 6:40 a.m. CDT. The vehicle went through the median, then became airborne for 109 feet before crashing.

"He never hit the brakes," Oklahoma Highway Patrol Trooper Betsy Randolph said.

A male passenger who was wearing his seat belt survived, police said. He was taken to a local hospital with injuries that were not life-threatening.

All the victims were believed to be illegal immigrants. Randolph said some of the victims carried identification, but none had a driver's license. She said troopers will work with a consulate from Mexico to help find their families.

In January, another crash on the highway about two miles away killed seven illegal immigrants whom federal immigration authorities said were being smuggled from Arizona to North Carolina. In that accident, a van hit a patch of ice on the highway, slid across the center median and slammed into an oncoming tractor-trailer.