The body of 20-year-old Yoo Siriratchanon was caught in a fishing net belonging to a trawler named Jit Roongroj 4 about 4.5 kilometres off the coast of Don Sak district at about 3am on Sunday, Pol Capt Thepsingha Thepluen said.
Yoo was being escorted by his mother, Kanokwan Jittalarn, and family members from the island on Seatran ferry on Saturday afternoon to meet a doctor at Suansaranrom Psychiatric Hospital in Phunphin district of Surat Thani when he ran from the passenger compartment and plunged into the sea about seven kilometres off the mainland port of Don Sak.
Passengers and crew threw life vests into the sea before he went under, Mrs Kanokwan said. Rescue workers were dispatched to the area but strong waves in the Gulf of Thailand impeded attempts to locate the man.
Mrs Kanokwan said her son had experienced mental problems and had drunk toilet cleaner to kill himself but was saved at the hospital in time. He recently suffered from depression, she said, and the family were taking him for treatment when he jumped off the ferry.