A minivan that authorities suspect was being used to smuggle illegal immigrants crashed on a highway Tuesday, killing four people and putting 10 in the hospital, police said. The driver fled on foot.

None of the injuries appeared to be life-threatening, a hospital spokesman said.

The van lost control on a curve on Interstate 70, struck a tree and rolled, ejecting most of the occupants, said Ron Watkins, Colorado State Patrol master trooper. Snow had fallen in the area, about 20 miles west of Denver, but the roads were in good condition, he added.

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The driver fled, and a search was under way, Watkins said.

A spokesman for Immigration and Customs Enforcement said the van is suspected of being involved in immigrant smuggling.

The van "fits the pattern" of illegal immigrant smuggling because of the number of people it was carrying, Watkins said. He had no information on the occupants' citizenship.

Nine adults and one minor were being evaluated at St. Anthony Central Hospital in Denver, spokeswoman Bev Lilly said.

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