Mark Zuckerberg acknowledges mistakes, apologises over data misuse

Facebook chief Mark Zuckerberg vowed on Wednesday to "step up" to fix problems at the social media giant, as it fights a snowballing scandal over the hijacking of personal data from millions of its users.

The world's largest social media network is facing growing government scrutiny in Europe and the US about a whistleblower's allegations that London-based political consultancy Cambridge Analytica improperly accessed user information to build profiles on American voters which were later used to help elect US President Donald Trump in 2016.

"We have a responsibility to protect your data, and if we can't then we don't deserve to serve you," Zuckerberg said, in his first public comments on the harvesting of Facebook user data by a British firm linked to President Donald Trump's 2016 campaign.

Zuckerberg announced new steps to rein in the leakage of data to outside developers and third-party apps, while giving users more control over their information through a special toolbar.

"This was a major breach of trust and I'm really sorry that this happened," Zuckerberg said in a televised interview with CNN.

"Our responsibility now is to make sure this doesn't happen again."

TRT World's Sally Ayhan has more.

Chief Operating Officer Sheryl Sandberg said she deeply regretted "that we didn't do enough" on Cambridge Analytica. "We've spent the past few days working to get a fuller picture," she said.

Zuckerberg promised steps to "prevent bad actors from accessing people's information" and said the company is working with regulators as they investigate what happened.

Stocks take hit

The company has lost more than $45 billion of its stock market value over the past three days after news reports detailing the allegations were published at the weekend.

Facebook shares closed up 0.7 percent on Wednesday, but are still down more than eight percent since Friday. 

The company has risen more than 550 percent in value in the past five years.

Fears that a failure by big tech firms to protect personal data could deter advertisers and users and invite tougher regulation has also hit the shares of Twitter and Snapchat.

On Tuesday, the board of Cambridge Analytica suspended its Chief Executive Alexander Nix, who was caught in a secret recording boasting that his company played a decisive role in Trump's victory.

But the academic who provided the data disputed that on Wednesday.

"I think what Cambridge Analytica has tried to sell is magic, and they've made claims that this is incredibly inaccurate and it tells you everything there is to tell about you. But I think the reality is it's not that," psychologist Aleksandr Kogan, an academic at Cambridge University told the BBC in an interview broadcast on Wednesday.

Kogan, who gathered the data by running a survey app on Facebook, also said that he was being made a scapegoat by Facebook and Cambridge Analytica. Both companies have blamed Kogan for alleged data misuse.

Only 300,000 Facebook users responded to Kogan's quiz, but that gave the researcher access to those people’s Facebook friends as well, who had not agreed to share information, producing details on 50 million users.

Facebook has said it subsequently made changes that prevent people from sharing data about friends, and maintains that no data breach occurred because the original users gave permission. Critics say that it essentially was a breach because data of unsuspecting friends was taken.

Facebook bans Cambridge Analytica

Zuckerberg said on Wednesday the company "will restrict developers' data access even further to prevent other kinds of abuse."

Facebook banned Cambridge Analytica from using any of Facebook's services on Friday.

Many analysts have now raised concerns that the incident will have a negative impact on user engagement with Facebook, potentially reducing its clout with advertisers.