Galveston police received a call about a vehicle that drove through the chain and into the water at 21st Street and Harborside Drive around 1 a.m.
Investigators arrived and learned at least one man, identified as 21-year-old driver Caleb Joseph Hayes, managed to escape from the submerged vehicle.
Hayes was taken to UTMB Health Galveston, where he was questioned and treated.
Port of Galveston Police and the U.S. Coast Guard started a search after Hayes told police three others were inside the sunken car, using helicopters, boats, and dive teams.
As of 6:15 a.m., police told ABC Houston affiliate KTRK that they had located the vehicle, but it was still underwater. According to Galveston PD, the vehicle was pulled from the water at 8:30 a.m., but no occupants were found.
According to a press release, it was later discovered that the three other presumed missing passengers had been found safe by officials and appeared not to have been inside the vehicle then.
Police said the driver was released from the hospital and subsequently charged with DWI.
An investigation is ongoing.