Geoffrey Hinton told The Guardian that AI could trigger a large-scale incident this year or next, such as a temporary blackout of financial or power systems.
He also said it could turn out that humans would have been better off never developing the technology.
Hinton, 78, won the 2024 Nobel Prize in Physics for his work on artificial neural networks, the technique behind modern AI.
He left his job at Google in 2023 so he could speak freely about the risks of AI.
He did not predict a specific event or date. His concern is that systems able to affect infrastructure are in use while the rules around them are still being written.
Hinton has put the chance that AI causes human extinction in the coming decades at 10 to 20 percent. Nvidia chief Jensen Huang has questioned that estimate.
In October he signed an open letter with about 400 scientists from 34 countries calling for an international body to set containment standards for AI.
The letter asked for limits on connecting capable models to the internet and for public reporting when containment fails.
Hinton says he is not a "doomer" and still thinks AI could lead to a "wonderful future" if it is developed with care.
He is the subject of a new documentary, "AI: Probably Nothing to Worry About", a title suggested by an AI chatbot.