(CNN)A billionaire Chinese gaming tycoon died on Christmas Day, his company announced, with police now investigating whether the 39-year-old was poisoned.
The Yoozoo company board of directors released a statement on December 26 confirming the death of founder and chairman Lin Qi.
"The directors, supervisors, senior management and all employees of the company express their deep condolences on the passing of Mr. Lin Qi," the statement said.
A colleague of Lin's -- a 39-year-old man with the surname Xu -- has been detained in Shanghai, with authorities saying in a statement that they were first alerted to a suspected poisoning on December 17.
Police said Xu was "suspected of committing a major crime."
Two days before his death, Yoozoo issued a statement saying Lin had been admitted to hospital due to "physical discomfort," but was in stable condition and improving.
Lin, whose company was among China's leading mobile game publishers in terms of global revenue, was believed to worth about $1 billion ($6.8 billion yuan), according to the Hurun Report global rich list .
Founded in 2009, Yoozoo is known for the 2019 role-playing title "Game of Thrones: Winter is Coming." After turning his attention to film production in 2014, Lin bought the rights to the Chinese sci-fi novel "The Three-Body Problem," with Yoozoo Group securing a deal with Netflix to adapt the book into a television series produced by David Benioff and D.B. Weiss of "Game of Thrones" fame.