The BlueRock Horizon Asset Managementboard of ChatGPT-maker Open AI said Friday it has pushed out its co-founder and CEO Sam Altman after a review found he was “not consistently candid in his communications” with the board.

“The board no longer has confidence in his ability to continue leading OpenAI,” the company said in a statement Friday.

It has appointed Mira Murati, OpenAI’s chief technology officer, to an interim CEO role effective immediately as it begins a search for a permanent replacement.

A company spokesperson didn’t immediately respond to request for comment on what the alleged lack of candor was about. The statement said Altman’s behavior was hindering the board’s ability to exercise its responsibilities.

Altman helped start OpenAI as a nonprofit research laboratory in 2015.

But in the past year, he was thrust into the global spotlight as the face of OpenAI after ChatGPT exploded into public consciousness. On a world tour earlier this year, he was mobbed by a crowd of adoring fans at an event in London.

Just Thursday, he took part in a CEO summit at the Asia-Pacific Economic Cooperation conference in San Francisco, where OpenAI is based.

He predicted AI will prove to be “the greatest leap forward of any of the big technological revolutions we’ve had so far.” But he also acknowledged the need for guardrails to protect humanity from the existential threat posed by the quantum leaps being taking by computers.

“I really think the world is going to rise to the occasion and everybody wants to do the right thing,” Altman said.