OpenAI said it has found a hidden recording device in one of its offices and has referred the matter to the FBI. One of its employees has been arrested.

In a statement on Tuesday, the San Francisco-based AI company said it discovered the “sophisticated recording device” and used one of its “models to understand the device and where it had come from”.

The company has identified “that a specific employee had planted it a few days earlier”, adding: “At this time, we have no indications of this individual inappropriately accessing or exfiltrating model weights, source code, or customer data. The employee was terminated.”

The employee in question has been arrested, according to the company. OpenAI did not disclose details on how its models were used to identify the employee or which office the device was discovered in.

OpenAI said that it is “grateful to the agents and prosecutors who moved quickly to make an arrest” and the investigation is continuing.

The company added: “We take protecting our technology, data, and people seriously, and as a matter of national importance. Our security program is designed to protect against a wide range of threat actors, from insider risks to cybercriminals to nation states, and this case is an example of how AI can help address these sophisticated security threats.”

The incident adds to a growing list of privacy controversies for OpenAI. In June, an agent hacked Australia’s university healthcare system, and earlier this month, California attorney general Rob Bonta issued an investigative subpoena to OpenAI over rogue hacking.

Last week, OpenAI announced it had terminated three safety researchers for allegedly sharing sensitive information in what the company called “a breach of trust”.

“They violated clear policies on handling sensitive information,” a company statement read.

The trio of researchers called on the company to adhere to its own promises of transparency made in the wake of the autonomous hacking incidents.

Meanwhile, Sam Altman, the OpenAI CEO, said in a recent interview that the world should accept “bad things” happening with AI in exchange for its benefits. Around the same time, David Robinson, a top safety leader resigned from the company, citing a “broken” company culture and warning that AI developers are not “being nearly careful enough” with the rapidly advancing technology.