TOPPENISH, Wash. — Traffic on U.S. Highway 97 was restricted for nearly six hours Monday when a milk truck rolled onto its side after striking a vehicle that ran a stop sign, authorities said.

The accident happened about a mile south of Toppenish.

Troopers said Michael Stiles 54, of Portland was driving a 2013 Kenworth south on U.S. Highway 97 about 10:10 a.m. when the driver of a 2001 Ford Escape failed to stop at the stop sign on Larue Road. The Ford hit the tractor-trailer combination, which turned over and spilled an unknown quantity of milk on the roadway. About 50 gallons of diesel fuel also leaked from the rig.

The Ford’s driver — 27-year-old Maximillian Becker of Grandview was not hurt, according to a patrol news release. Stiles was taken to Toppenish Community Hospital, where he was in satisfactory condition.

Troopers said Becker was expected to receive a ticket for failing to yield.

Both drivers were wearing seat belts. Intoxicants were not suspected of contributing to the crash, authorities said.

Because the truck blocked the northbound lane, traffic had to be diverted until about 4 p.m.