Karl Slym, managing director of India's Tata Motors Ltd, died after falling from a hotel room in Bangkok in what police said could be a possible suicide.
Slym, 51, had attended a board meeting of Tata's Thailand unit in the Thai capital and was staying with his wife in a room on the 22nd floor of the Shangri-La hotel. Hotel staff found his body on Sunday on the fourth floor, which juts out above lower floors.
Police Lieutenant Somyot Boonyakaew, who is heading the investigation, said there was nothing to suggest anyone else was involved.
"We are now waiting for the autopsy result. But after checking the scene, our preliminary investigation finds that it was a suicide because there is no evidence to connect it to murder," he said.
An autopsy on Slym's body was expected to begin on Monday.
Police found a three-page note, written in English, which they were translating into Thai.
Somyot said hotel staff had given him a rough translation of the contents of the note.
"We found a note in his room. From the rough translation from the hotel staff, he and his wife were having some arguments and that they had been living together for a long time, but there was a question of trust between the couple," he said.
A spokeswoman for Tata Motors, India's biggest automaker, declined to comment on the possible cause of Slym's death. A company statement on Sunday said Slym had provided leadership in a challenging market environment.
Slym, a British national, was hired in 2012 to revive Tata's flagging sales and market share in India. Tata Motors is part of the Tata conglomerate.
Tata Motors recently introduced a new petrol engine for its passenger vehicles and was planning to launch a hatchback and compact sedan this year, the first all-new Tata-branded passenger vehicles since 2010.
Slym led the vehicle maker's operations in India and international markets including South Korea, Thailand and South Africa, but he did not look after the Jaguar and Land Rover luxury unit that Tata Motors acquired in 2008.
The Thai police said they were called to the Shangri-La hotel around 7:45 a.m. on Sunday after staff found Slym's body. They woke up Slym's wife, who looked shocked when she was told what had happened to her husband.
Tata Motors had lost traction in the Indian passenger vehicle market as domestic and foreign rivals rolled out new models while it mostly tweaked existing ones and offered heavy price discounts.
The firm has not had a hit car at home since 1998. Sales of the Nano, the world's cheapest car which it unveiled in 2008, have been lackluster.
Before joining Tatar Motors, Slym was executive vice president of SGMW Motors, China, a General Motors joint venture. Before that he had headed General Motors in India.