TUSTIN, Calif.—A suspected copper wire thief was struck and killed on Oct. 2 after running across the Costa Mesa 55 Freeway away from police in Tustin.

The 32-year-old Santa Ana man’s name was not immediately released because authorities have not yet notified all of his family members, California Highway Patrol Officer Anselmo Templado said.

About 11:25 a.m., the suspect was stealing copper wire from a building “in broad daylight, throwing it to the ground” near First Street and Yorba Avenue, Tustin police Lt. Ryan Coe said.

The suspect was pushing a shopping cart of the copper from the scene when officers were arriving, Mr. Coe said. Apparently when he saw the officers he “ditched the stolen property, jumped a side of fence to the side of the freeway,” Mr. Coe said.

While officers were setting up a perimeter to contain the suspect he decided to dart across the freeway and was struck by a car in the northbound lanes at First and Fourth streets, Mr. Coe said.

Authorities had to block all lanes for about 30 minutes, Mr. Templado said. But as of 1:15 p.m., the three right lanes were open again, Mr. Templado said.