May 11 (UPI) -- Google announced Monday that it identified a cyber threat it believes hackers developed using artificial intelligence, meant to exploit networks on a large scale.

Google Threat Intelligence Group said the hackers were using a zero-day exploit, a security vulnerability that is unknown to security companies, and planned to use it for mass exploitation.

Google said this is the first time it has identified a threat with evidence that AI was used to develop it.

"AI-enabled malware, such as PROMPTSPY, signal a shift toward autonomous attack orchestration, where models interpret system states to dynamically generate commands and manipulate victim environments," Google Threat Intelligence Group said in a news release.

Google's AI Gemini and Claude Mythos were highlighted as AI models it does not believe were used in this threat attempt.