A senior Anthropic safety researcher has said there is more than a 10 percent chance artificial intelligence “could kill all humans” by the end of the decade, just hours after a colleague resigned over fears the AI lab and its rivals are carelessly racing to build “superhuman systems” they cannot control.

In a post on X announcing his departure, Jacob Coxon, a researcher who has trained AI systems at Anthropic, said he had quit the company over its lax approach to safety. Coxon, who previously trained systems for OpenAI, accused the two AI companies of “racing straight to self-improving superintelligence and gambling with our lives,” even though “the people building AI earnestly believe that it could kill us all by the end of the decade.”

Industry insiders have long expressed concerns about the potential dangers of self-improving AI systems, which they warn could spiral out of human control in a runaway loop often described as recursive self-improvement. While not yet realized, companies are actively pursuing this goal and much of today’s AI code is written with the help of AI.

In a direct response, Evan Hubinger, who leads one of Anthropic’s AI safety teams, said he worries about self-improving AI, adding that it “is happening faster than we thought.” He also agreed with Coxon’s characterization. “We really do earnestly believe AI could kill all humans,” he said, personally estimating the chances to be greater than one in 10 “within the next decade.”

Despite this, Hubinger said Anthropic does “not yet have a plan” for ensuring advanced AI remains safe and aligned with human values and “are not clearly on track to” develop one either. Coxon says the companies are “locked in a race” to develop advanced systems first so are pushing ahead “despite the risk.”

Coxon’s departure marks one of the most high profile examples of an employee leaving Anthropic, a company founded by former OpenAI members following concerns over safety at the company. In recent years, multiple researchers have cited safety concerns as motivating their decision to leave OpenAI.