SHELTON, Wash. -

Searchers from Thurston, Pierce and Mason counties are searching for a 10-year-old boy who disappeared Thursday while picking berries near Lake Cushman in Mason County.

The sheriff's office says the family was camping and Nathan Hernandez was picking berries with his sisters when they lost sight of him. The family searched for him until dark and then called for help.

The sheriff's office says searchers have been using dogs and heat-detecting technology in the overnight search.