single-engine plane (search) trying to make an emergency landing on a freeway Saturday clipped a van and flipped upside down, and the pilot was arrested for flying under the influence of alcohol, authorities said.

Pilot Marc South (search), 53, of Eloy, Ariz., was treated for minor injuries before being taken into custody, the Los Angeles County Sheriff's Department said in a statement.

South was administered a sobriety test, said Officer Brian Joy of the California Highway Patrol. His blood-alcohol level was not released but Joy noted that pilots are subject to tougher standards. The legal level for pilots is below .04 percent. For drivers, the legal limit is .08 percent.

South told investigators his plane's engine died and he began making an emergency landing on northbound lanes of Interstate 5. Drivers slowed down to make way but South lost control when the plane's wing clipped a van, said Officer Brian Joy of the California Highway Patrol.

The driver of the van, 58-year-old David White, was not injured.

"I had my driver's side window up and it smashed right into it," White told KNBC-TV.

South's two-seat Ercoupe (search) was headed from La Verne to Sacramento, said Diana Joubert, regional operations officer for the Federal Aviation Administration. The plane, which Joubert said was heavily damaged, was removed from the scene.