The Fresno Co. Sheriff's Department says the break in this case came Wednesday evening when a woman reported finding a cold and hungry man near Kerman who claimed to be Ryan Rodriquez.
A co-worker of Rodriquez' told investigators they last saw him on Friday around 10:30 in the morning.
Rodriquez was driving a water truck near the intersection of Oakland and Butte Avenues, 12 miles north of Huron.
The 32-year went to refill his truck, but was never seen again.
Co-workers went searching for him and only found his truck parked next to the water pump.
A sheriff's lieutenant talked about what their top priority is right now.
"We're trying to determine if there was a crime involved and if there are any suspects that need to be searched for at this time," said Lt. Louis Hernandez.
The lieutenant described Rodriquez as being in fair condition in terms of health.
Detectives are interviewing him to try and piece together the details of his disappearance and if any foul play was involved.
Rodriquez' return comes on the day his family increased his missing person reward from $20,000 to $100,000.