The 58-year-old welder injured during an explosion on board a tanker docked for repairs at Keratsini was still being treated in KAT hospital on Friday morning, one day after the accident.
Early reports said the accident was caused by a gas leak from the rubber piping of the oxyacetylene torch he was handling.
Authorities have so far arrested the foreman and safety technician placed in charge of work on the ship by the company carrying out the repairs, aged 59 and 56 respectively. Both were temporarily released by order of a public prosecutor, who ordered a preliminary investigation to be handled by the Keratsini coast guard.

The unlucky welder suffered second-degree burns on 60 percent of his body when an explosion occurred as he was cutting metal pipes with an oxyacetylene blow torch.