The former chief executive of Cambridge Analytica allegedly withdrew $8 million from the data consulting firm before it shut down in the wake of Facebook data breach scandal.

The Financial Times on Wednesday reported that Alexander Nix banked the money for "unbooked services" after the first media reports in March revealed that London-based Cambridge Analytica had illicitly harvested 87 million Facebook accounts to target voters during Donald Trump's successful 2016 presidential campaign. Cambridge Analytica announced on May 2 that it had ceased operations and declared bankruptcy.

Cambridge Analytica and a sister company, SCL Group, had raised $19 million from international investors to launch Emerdata, a successor company. Emerdata's board included Rebekah and Jennifer Mercer, daughters of right-wing hedge fund tycoon and prominent Trump donor Robert Mercer, who had also helped bankroll Cambridge Analytica.

Mercer also funded controversial right-wing news site Breitbart. Steve Bannon, Breitbart's former executive chairman and former White House advisor, once sat on the board of Cambridge Analytica.

Bankruptcy filings in New York showed that Cambridge Analytica received an $8.8 million loan from Emerdata before it entered administration in May, the FT revealed.

Citing several sources, the FT reported that Emerdata investors are now demanding Nix repay the missing millions. They added that they would also like former Cambridge Analytica employees to receive redundancy pay after they were dismissed without severance pay.

Nix, 43, did not respond to numerous requests for comment from the FT, but according to some people involved in the dispute, he has indicated that he intends to repay part on the money.

Another Emerdata company director is Johnson Chun Shun Ko, the deputy chairman of Frontier Services Group, a Hong Kong-based integrated security firm with major interests in Africa. Frontier is also chaired by another prominent Trump supporter, Erik D. Prince, a former U.S Navy Seal, who founded the private military group Blackwater USA and is the brother of Secretary of Education Betsy DeVos.

Prince also donated to the Make America Number 1 PAC, a Mercer-backed fund group that supported Trump's presidential campaign.

Meanwhile, Nix has agreed to appear before Parliament's media committee after previously refusing to testify due to law enforcement investigations into the firm.

Earlier this week, U.K. Information Commissioner Elizabeth Denham told the European Parliament she was "deeply concerned" about the impact on democracy of the misuse of social media users' personal information. She said legal systems had failed to keep up with the rapid development of the internet.