An auto dealer and car-racing businessman reportedly turned a gun on himself in his Bangkok condominium room on Thursday morning, police said.
Police said Parithat Poolphol, 45, managing director of Grand Eastern Co Ltd and Racing Spirit Co Ltd, shot himself with a 9mm pistol.
Police said he left a suicide note, saying he was under pressure because of his work.
He lived with his 20-year-old daughter. The daughter, who was in another room, heard the gunfire at 9.45am.
Racing Spirit has organised several racing events and is building a motor racing facility in Chon Buri with the budget of Bt4 billion.
It was later found that Parithat also recorded a clip on his cell phone talking about which of his assets would go to whom as an audio will.