SAN FRANCISCO, March 21 (Xinhua) -- Facebook CEO Mark Zuckerberg admitted on Wednesday that his company has made mistakes in a data leak that caused grave concern about user privacy possibly abused for political purposes.

"We also made mistakes, there's more to do, and we need to step up and do it," he said in a statement.

Facebook has been plunged into a turmoil after U.S. and British media reported that the data of more than 50 million Facebook users were inappropriately used by a British data analysis company, Cambridge Analytica, in activities allegedly connected with U.S. President Donald Trump during his 2016 campaign.

Zuckerberg said Facebook will take measures to prevent this from happening again.

"I've been working to understand exactly what happened and how to make sure this doesn't happen again," he said.

The world's largest social media company suffered the biggest one-day drop of its stocks by 7 percent on Wall Street on Monday in four years following the reported data leakage.

Also on Monday, Facebook announced on Monday that it has hired digital forensics firm, Stroz Friedberg, to investigate the alleged leakage of its users' data.