A 9-year-old boy riding with his father in a semitrailer truck died in an early-morning collision on a western Wisconsin highway, authorities said.

The crash occurred shortly before 4 a.m. Sunday on Hwy. 8 west of Barron, according to the Barron County Sheriff's Office.

Alex Olmsted, of Clintonville, Wis., was trapped underneath the semi and died at the scene, the Sheriff's Office said.

The boy's father, 48-year-old Jerald Olmsted, was removed from the wreckage and hospitalized with severe injuries.

The driver of the other vehicle, 22-year-old Nicholas Rogalla, of nearby Rice Lake, was hospitalized and was expected to survive his injuries.

According to the Sheriff's Office:

Rogalla was driving his car on eastbound Hwy. 8 and crossed into the path of the westbound semi, a tanker hauling a full load of milk. The collision sent the truck rolling into the ditch.

Cleanup from the wreckage and investigation of the crash had the highway closed for more than 8 hours.

Paul Walsh • 612-673-4482