OpenAI on Tuesday said it had slowed down the pace of its AI development while it overhauled its research and training systems.

The company’s researchers were caught unaware last month when an AI agent under testing hacked another AI firm.

The AI research lab behind ChatGPT said its new measures included pausing its model testing for two weeks and investing more in adding other AI systems to monitor the activities of AI agents in testing. Some of the company’s largest planned training runs remain on hold, the company said.

The company did not reply to questions about when the slowdown began or when it planned to return to its normal pace of development. However, in an interview with tech blog Sources News, Mia Glaese, who leads safety at Open AI said: “We are very far from everything running back to normal.”

The company is working to ensure the AI model is responsive to human oversight and will behave as intended, a process called alignment, Sam Altman, the OpenAI CEO, wrote in the post announcing the slower pace of development.

“We now require stronger evidence of aligned behavior throughout all of training, building on research and evaluations already underway,” he wrote. “Keeping increasingly capable systems aligned is a challenge the whole field will need to address.”

The announcement comes a week after Bernie Sanders, a Vermont senator, demanded the top AI firms in the country pause development of the AI models because the companies were losing control over the technology, he wrote in a letter addressed to the firms’ CEOs.

“Mr. Altman, Mr. Amodei and Mr. Zuckerberg: In the interest of humanity, stand by your words. Pause AI development,” Sanders’s letterread.

By then, OpenAI had announced that it was temporarily slowing the development of its latest model, Astra, in response to the model’s hack of HuggingFacetech firm, HuggingFace.

The company says it now requires “the strictest level of security safeguards for workloads involving Astra”.

“While some Astra training and evaluations meet those requirements, a significant number of workloads remain paused until they are fully migrated and enhanced to meet the new security bar,” the announcement reads.