A person may have been behind the wheel of a truck found submerged in the water in a Carlsbad jetty.
Officers found the pickup in the water on the east side of Carlsbad Boulevard south of Tamarak.
Lifeguards did a sweep inside the truck just after midnight. One of the windows was rolled down but no one was inside, police said.
At 10:26 a.m., the truck was towed out of the water.
After an investigation, police said it was a citizen on the side of the road who flagged down a police patrol car to report the truck in the water.
The truck is believed to have entered the lagoon at Garfield Street, police said.
According to Carlsbad Police, the registered owner lives in Oceanside and was contacted by Oceanside PD Wednesday morning.
He told police he left his keys inside the truck and that it was stolen Tuesday night.
No other information was immediately available.
The San Diego Sheriff's Department Dive Team will go back to the area at low tide to search for any possible victims.