UPDATE (July 23, 18:19 UTC): In a Periscope video broadcast live Tuesday afternoon, Justin Sun appeared to be in San Francisco (with the Bay Bridge in the background), and not in China, as news outlet Caixin reported earlier.

UPDATE (July 23, 2019, 16:50 UTC): Chinese business news organization Caixin reported Tuesday that Justin Sun is under Chinese government control, meaning he is not allowed to leave the country pending an investigation. He is not facing formal charges at this time.

A local internet finance risks regulator has also recommended that police form a case against Sun.

Justin Sun’s hotly-anticipated lunch with billionaire investor Warren Buffett has been postponed, the Tron Foundation announced Monday.

Sun has fallen ill with kidney stones, the foundation said on Twitter. The parties have “agreed to reschedule at a later date.”

The lunch, scheduled for July 25, was the prize for winning a charity auction. Sun bid $4.6 million earlier this year and seemingly intended to introduce the notoriously crypto-skeptical Buffett to a number of influential figures in the space.

As of Monday, Sun had lined up Circle’s Jeremy Allaire, Huobi’s Chris Lee, eToro’s Yoni Assia and litecoin creator Charlie Lee to join him.

The specific subjects to be discussed during the steak meal were not disclosed; however, Buffett has famously called bitcoin “rat poison squared,” and made a number of other unflattering remarks about cryptocurrencies.

Sun, himself a controversial figure, is the creator of the Tron cryptocurrency and head of its namesake foundation. He convinced Buffett to move the charity lunch from its traditional New York location to Silicon Valley.

Justin Sun at Consensus 2019, image via CoinDesk archives