Twitter whistleblower Peiter Zatko’s disclosures reveal that there was at least one Chinese agent working at the microblogging platform, according to a report quoting a US Senator during a hearing where the whistleblower is set to begin testifying before a US Senate Committee. The whistleblower, who previously worked as Twitter’s security chief, has made allegations of serious security flaws at the company. The hearing will take place a month before Twitter faces off with Tesla CEO Elon Musk in court over his decision to walk away from the $44 billion (roughly Rs. 3,49,900 crore) takeover deal.

According to a report by Reuters, US Senator Chuck Grassley’s opening remarks on Tuesday at the Senate hearing revealed that disclosures from Zatko indicated that at least one Chinese agent was employed at the company. The popular hacker is scheduled to provide testimony about his allegations against his former employer.

It was previously reported that Zatko had alleged that Twitter had misled the US Federal Trade Commission (FTC) about the company’s security measures as part of an agreement in 2011. He has also alleged that Twitter has serious security flaws affecting the platform, and that one or more employees were working on behalf of foreign governments.

Twitter has previously stated that the allegations from Zatko, who was fired for “ineffective leadership and poor performance,” appeared to be designed to harm the company.

The company’s shareholders are expected to vote on the takeover deal by Tuesday, ahead of the upcoming trial next month, when the company will face of with Tesla CEO Elon Musk in court on October 17.