The United Kingdom's data watchdog has confirmed it has applied for an urgent warrant to raid the London headquarters of Cambridge Analytica, the firm at the heart of a scandal over revelations that it gained unauthorised access to tens of millions of Facebook profiles.
Speaking on Tuesday, U.K. Information Commissioner Elizabeth Denham branded the firm "uncooperative" and confirmed that she is seeking a warrant to access data held by the firm.
The statement came as the House of Commons digital, culture, media and sport committee requested that Mark Zuckerberg, chief executive of Facebook, appear urgently before the committee's Fake News inquiry over what it called a "catastrophic failure of process", accusing the company of "misleading" the committee in a previous hearing.
The committee announced it would be taking evidence from former Facebook operations manager Sandy Parakilas tomorrow by video link.
On Monday night, consultants from the digital forensics firm Stroz Friedberg, which Facebook reportedly hired to do the audit, were at Cambridge Analytica's London office. The Information Commissioner's Office (ICO) asked them to leave, so that authorities could pursue their own investigation.
The ICO statement confirmed that it had asked Facebook to stand down its search of Cambridge Analytica, as "such a search would potentially compromise a regulatory investigation".
On Tuesday morning, the data firm's London headquarters appeared to be on lockdown, with a security guard strictly monitoring those entering.
As Cambridge Analytica chief executive Alexander Nix entered the building, he was asked about the explosive undercover footage broadcast by Channel 4 on Monday evening, in which he was caught explaining he could use sex workers to compromise politicians.
Nix responded by saying that "appearances can be deceptive". When asked whether he had misled Parliament when he gave evidence to a select committee on the firm's practices, he said: "Absolutely not."
Not long after Nix entered the building, HuffPost UK saw around 10 crates filled with files and documents being assembled in the lobby of the building. Their provenance is unknown.
When two men loading the materials into a rental delivery van were asked if they were working for Cambridge Analytica, they refused to comment.
Nix said they could "send some girls around to the candidate's house", adding that Ukrainian girls "are very beautiful, I find that works very well", Channel 4 reported.
Cambridge Analytica, which provided services to Donald Trump's election campaign, said the report was "edited and scripted to grossly misrepresent" the way the company conducts its business.
The firm said it routinely undertook conversations with prospective clients to "tease out any unethical or illegal intentions", and the executives "humoured" the reporter's questions.
But Nix said: "In playing along with this line of conversation, and partly to spare our 'client' from embarrassment, we entertained a series of ludicrous hypothetical scenarios.
"I am aware how this looks, but it is simply not the case. I must emphatically state that Cambridge Analytica does not condone or engage in entrapment, bribes or so-called 'honeytraps', and nor does it use untrue material for any purpose.
"I deeply regret my role in the meeting and I have already apologised to staff.
"I should have recognised where the prospective client was taking our conversations and ended the relationship sooner."
Cambridge Analytica was suspended from Facebook last week after it emerged that data on millions of users had not been destroyed as agreed.
Whistleblower Chris Wylie, a former research director at the U.K.-based company, told Channel 4 News a so-called data grab had been carried out on more than 50-million profiles in 2014.
Damian Collins, chairperson of the House of Commons digital, culture, media and sport committee, has called on Facebook founder Mark Zuckerberg to appear before MPs to explain his company's actions.
Asked about the reports, U.K. prime minister Theresa May's spokesperson said: "The allegations are clearly very concerning.
"It is essential that people can have confidence that their personal data will be protected and used in an appropriate way.
"It is absolutely right that the information commissioner is investigating this matter.
"We expect Facebook, Cambridge Analytica and all the organisations involved to cooperate fully."
The ICO is investigating the use of personal data for political campaigns, including the activities of Cambridge Analytica.
Denham said: "This is a complex and far-reaching investigation for my office, and any criminal or civil enforcement actions arising from it will be pursued vigorously."