'That was a mistake': Facebook founder Mark Zuckerberg grilled over Cambridge Analytica
After breaking his silence on the Cambridge Analytica scandal on Thursday, Facebook founder Mark Zuckerberg gave an interview on US television saying he was "really sorry this happened".
Echoing his earlier Facebook post, and stopping short of apologising outright, Zuckerberg said he regretted that the company did not inform people of the data breach at the time.
Zuckerberg said the company was unaware of the data breach before Guardian journalists informed them in 2015, and only last week learnt through The Guardian, The New York Times and Britain's Channel 4 that Cambridge Analytica "may not have deleted this data as certified".
"I’m used to, when people legally certify they're going to do something, that they’ll do it, and that was a mistake," he said in the interview with CNN.
However, he admitted there "probably were signs that we could have looked into".
Zuckerberg said the company was launching a "full investigation" into every app that had access to user data before Facebook changed its policy in 2014.
When asked whether that task would be difficult, he said the company already knows what those apps are.
"We'll be able to do a full audit," he said.
"It’s hard to know what we’ll find but we're going to review thousands [of apps].
"We need to make sure there are not any other Cambridge Analyticas out there."
Zuckerberg said Facebook would also be informing everyone whose data might have been affected.
The data collected, partially viewed by The New York Times, included users' friends, identities and "likes".