Frustrated by Facebook CEO Mark Zuckerberg’s refusal to answer questions from MPs, the UK Parliament has used its legal powers to seize internal Facebook documents relating to the Cambridge Analytics scandal, The Observer reports.

The documents are thought to include confidential emails between senior executives, and correspondence with Zuckerberg. They are also thought to explain how user data decisions were made in the years before the Cambridge Analytica breach, including what Zuckerberg and senior executives knew.

According to the Observer report, Damian Collins, the chair of the culture, media and sport select committee, invoked a rare parliamentary mechanism to compel the founder of a US software company, Six4Three, to hand over the documents during a business trip to London. In another exceptional move, parliament sent a serjeant at arms to his hotel with a final warning and a two-hour deadline to comply with its order. When the software firm founder failed to do so, it’s understood he was escorted to parliament. He was told he risked fines and even imprisonment if he didn’t hand over the documents.

The documents seized were obtained during a legal discovery process by Six4Three. It took action against Facebooko after investing $250,000 in an app. Six4Three alleges the cache shows Facebook was not only aware of the implications of its privacy policy, but actively exploited them, intentionally creating and effectively flagging up the loophole that Cambridge Analytica used to collect data. That raised the interest of Collins and his committee.

“We are in uncharted territory,” Collins, told the Observer. “This is an unprecedented move but it’s an unprecedented situation. We’ve failed to get answers from Facebook and we believe the documents contain information of very high public interest.”

Collins added that it was Zuckerberg’s reluctance to testify, plus misleading testimony from a Facebook executive at a hearing in February, that had forced MPs to explore other options for gathering information about Facebook operations.

“We have very serious questions for Facebook. It misled us about Russian involvement on the platform. And it has not answered our questions about who knew what, when with regards to the Cambridge Analytica scandal,” Collins said.