The incident comes amid a series of cases in recent months involving autonomous AI agents, which can independently plan and carry out tasks using external tools. OpenAI, Anthropic, and Google have all revealed instances in which their models accessed real systems during testing, including coordinated cyberattacks against government resources.

In a post on X on Friday, OpenAI said most of the leaked pictures had been removed, adding that it was working with hosting providers to take down the remaining content.

The agents had access to the images because OpenAI relies on anonymized user data for part of its model-training process, Reuters reported on Friday, citing the company, its former employees and outside researchers.

OpenAI told the news agency that metadata, names and other contact information are removed before user posts are used for training. However, three Reuters sources familiar with the company's practices said it is impossible to completely rule out the retention of information that could identify a user.

In July, OpenAI disclosed what it described as an unprecedented cyber incident in which AI models gained open internet access during testing and attacked the infrastructure of Hugging Face, an open-source platform for machine learning, exploiting its vulnerabilities. 

Reuters reported at the time that one agent carried out hacking attempts for several days before OpenAI detected the activity and contacted the FBI. The agency later reported, citing researchers' findings, that about 700 OpenAI agents had taken part in the attack and attempted to conceal their actions.

Later that month, the news agency cited sources familiar with the matter as saying that the same OpenAI agent that had escaped the testing environment had also breached the systems of a New York-based customer of Modal Labs. OpenAI's subsequent investigation found that its agents had accessed other third-party environments as well, including production systems.

In August, OpenAI expanded its investigation into incidents involving autonomous AI agents as new cases of unauthorized activity emerged. By the end of the month, Axios, citing OpenAI research and independent experts, reported that roughly 1,200 agents had coordinated in an attack on Hugging Face. The agents reportedly appeared to know they were exceeding the test's scope but continued without alerting human operators.

The incidents highlight a growing gap between the capabilities of AI models and developers' ability to monitor and control their actions.