OLYMPIA, Wash. —  A woman heading to her stepfather's house was "beyond lost" when she and her 8-year-old son took one wrong turn after another through the backroads of Washington state and onto a private Puget Sound beach, authorities said Monday.

The minivan driven by Shantina Smiley was found partially submerged Sunday with its doors open. A wallet containing the 29-year-old's driver's license, some cash and credit cards was found in the van, but neither she nor her son was anywhere in sight.

"Apparently she got stuck and abandoned the car," said Lt. Chris Mealy of the Thurston County Sheriff's Office. There was no indication that a crime took place inside the 2005 Dodge Caravan, he added.

Divers searched the water off the beach on Monday while bloodhounds on loan to the sheriff's office scoured the nearby roadside.

Detectives have traced Smiley's path from her home in Silverdale to the far reaches of Thurston County, more than 50 miles north of her stepfather's house in Castle Rock in Cowlitz County and far from any road that would have led her there.

Mealy said Smiley had called her fiance Saturday night in Olympia to update him on her location because she had left her cell phone at home. An employee at an Olympia diner where she bought a corn dog told investigators she left without her purchase and then tripped and fell walking back to her van, but Mealy said the fall was not serious...