Orange County sheriff's Lt. Jason Park says the search will center Wednesday on an area where mountain bikers reported seeing some kind of a light Tuesday night.
Nineteen-year-old Nicholas Cendoya and 18-year-old Kyndall Jack were last heard from Sunday night after they went for a hike in the Cleveland National Forest and called for help.
However, their cellphones have died.
Dozens of searchers aided by helicopters, dogs and horses have scoured the area.
