The three disappeared March 4 during a fishing and camping trip in a rural area north of Sacramento. Fishermen reported hearing a vehicle crash into the river.
Relatives said they were notified Sunday that authorities had recovered the remains of 18-year-old Roman Pristupa.
Sutter County Sheriff's Capt. Dave Samson says a second body was pulled from the river Sunday and is presumed to be one of the other two teens.
Friends and family have identified the other missing youths as 17-year-old Aleksandr Kaplinsky and 16-year-old Bohdan Lytvynyuk.
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