LONDON, England (AP) — A British parliamentary committee yesterday summoned Facebook CEO Mark Zuckerberg to answer questions as authorities stepped up efforts to determine if the personal data of social media users has been used improperly to influence elections.

The request comes amid allegations that a data-mining firm based in the UK used information from more than 50 million Facebook accounts to help Donald Trump win the 2016 Presidential Election. The company, Cambridge Analytica, has denied wrongdoing.

However, the firm’s board of directiors announced yesterday evening that it had suspended CEO Alexander Nix, pending an independent investigation of his actions. Nix made comments to an undercover reporter for Britain’s Channel 4 News about various unsavoury services Cambridge Analytica provided its clients.

“In the view of the board, Nix’s recent comments secretly recorded by Channel 4 and other allegations do not represent the values or operations of the firm, and his suspension reflects the seriousness with which we view this violation,” the board said in a statement.

Facebook also drew continued criticism for its alleged inaction to protect users’ privacy. Earlier yesterday, chairman of the UK Parliamentary media committee, Damian Collins said his group has repeatedly asked Facebook how it uses data and that Facebook officials “have been misleading to the committee”.

“It is now time to hear from a senior Facebook executive with the sufficient authority to give an accurate account of this catastrophic failure of process,” Collins wrote in a note addressed directly to Zuckerberg. “Given your commitment at the start of the new year to ‘fixing’ Facebook, I hope that this representative will be you.”

Facebook sidestepped questions on whether Zuckerberg would appear, saying instead that it’s currently focused on conducting its own reviews.

The request to appear comes as Britain’s information commissioner said she was using all her legal powers to investigate the social media giant and Cambridge Analytica.

Commissioner Elizabeth Denham is pursuing a warrant to search Cambridge Analytica’s servers. She has also asked Facebook to cease its own audit of Cambridge Analytica’s data use.

“Our advice to Facebook is to back away and let us go in and do our work,” she said.

Cambridge Analytica said it is committed to helping the UK investigation. However, Denham’s office said the firm failed to meet a deadline to produce the information requested.

Denham said the prime allegation against Cambridge Analytica is that it acquired personal data in an unauthorised way, adding that the Data Provisions Act requires services like Facebook to have strong safeguards against misuse of data.

Chris Wylie, who once worked for Cambridge Analytica, was quoted as saying the company used the data to build psychological profiles so voters could be targeted with ads and stories.

The firm found itself in further allegations of wrongdoing. Britain’s Channel 4 used undercover investigation to record Nix saying that the company could use unorthodox methods to wage successful political campaigns for clients.

He said the company could “send some girls” around to a rival candidate’s house, suggesting that girls from Ukraine are beautiful and effective in this role.

He also said the company could “offer a large amount of money” to a rival candidate and have the whole exchange recorded so it could be posted on the Internet to show that the candidate was corrupt.

Nix said in a statement that he deeply regretted his role in the meeting and has apologised to staff.

“I am aware how this looks, but it is simply not the case,” he said. “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 purposes.”

Nix told BBC the Channel 4 sting was “intended to embarrass us”.

“We see this as a coordinated attack by the media that’s been going on for very, very many months in order to damage the company that had some involvement with the election of Donald Trump,” he said.

The data harvesting used by Cambridge Analytica has also triggered calls for further investigation from the European Union, as well as federal and state officials in the United States.