Facebook is coming under growing pressure from lawmakers, regulators and investors across the globe over a revelation that data on millions of its users were abused.
The social-media giant was dealt several fresh blows on Tuesday, including a federal privacy investigation in Canada, renewed calls for its leaders to testify before political committees in the United States and Britain, an investor lawsuit in California, and a 2.5-per-cent decline in its stock.
Also on Tuesday, the data-mining firm at the centre of the controversy suspended its chief executive and promised an investigation.
The developments are the latest in what has become a growing political scandal for the Menlo Park, Calif.-based company, which is facing mounting criticism over fake news, political interference and its platform's role in elections in several countries.
Canada's Privacy Commissioner Daniel Therrien confirmed on Tuesday that his office is launching a formal probe into Facebook over reports that Cambridge Analytica, a UK political data-analysis firm hired by Donald Trump's election campaign team, had improper access to data from 50 million Facebook users
Mr. Therrien said his office was working to confirm with Facebook whether any users in Canada were affected. "The allegations we've seen in media reports raise extremely important privacy questions," he said in a statement. "The digital world, and social media in particular, have become entrenched in our daily lives and people want their rights to be respected."
In a statement, Facebook said: "We are strongly committed to protecting people's information and will answer any questions the Office of the Privacy Commissioner has."
The U.S. Federal Trade Commission, a consumer-protection and antitrust watchdog, is expected to launch its own inquiry into whether Facebook breached the terms of a 2011 settlement on data privacy, several U.S. media outlets reported.
A lawsuit filed by an investor on Tuesday in California says Facebook misled investors and failed to disclose that it gave third-party firms access to users' data.
The company's stock price has fallen nearly 10 per cent since The New York Times and the Observer of London published weekend reports that users' data were improperly collected and shared with Cambridge Analytica, a data-mining firm founded with money from wealthy Republican donor Robert Mercer and former Trump adviser Stephen Bannon.
Christopher Wylie, a Canadian who helped build Cambridge Analytica's data-analysis operations, told media outlets the firm received the personal information on Facebook users from Russian-American psychology professor Aleksandr Kogan. Dr. Kogan had created a Facebook personality quiz that harvested the data from users who authorized its app, as well as millions of their friends.
Facebook is under pressure to have its senior executives testify publicly before regulatory hearings. Days after the crisis erupted, neither Facebook's CEO, Mark Zuckerberg, nor its chief operating officer, Sheryl Sandberg, had issued public statements.
U.S. Senator John Thune, who chairs the Senate Commerce committee, was one of three Republican legislators to issue a letter to Mr. Zuckerberg requesting he respond by March 29 to questions about how Cambridge Analytica was able to access the data on U.S. voters. Facebook is expected to brief members of congressional intelligence, commerce and judiciary committees this week, NBC News reported.
In Britain, MP Damian Collins demanded that Mr. Zuckerberg respond to a request to appear in front of a British Parliamentary committee by March 26.
Facebook also confirmed it had stopped its search of Cambridge Analytica's offices at the request of the U.K.'s Information Commissioner, Elizabeth Denham. Ms. Denham is pursuing her own investigation into Cambridge Analytica as part of a broader probe into the use of data analytics for political purposes.
On Tuesday, the board of Cambridge Analytica said it had suspended CEO Alexander Nix and promised an independent investigation into comments he made to an undercover reporter on Britain's Channel 4 News suggesting the company had used unethical tactics such as bribes and prostitutes to entrap politicians and influence elections.
In the midst of the increasing battle with regulators, Facebook's chief information security officer, Alex Stamos, took to Twitter on Tuesday to deny reports he was about to leave the company because he had clashed with senior executives over how aggressively to pursue an investigation into Russian political interference on the platform.
"Despite the rumors, I'm still fully engaged with my work at Facebook," he wrote. "It's true that my role did change. I'm currently spending more time exploring emerging security risks and working on election security."
The British Information Commissioner Ms. Denham, a Canadian, was the assistant federal privacy commissioner in charge of a wide-ranging 2009 investigation into whether the way Facebook shared user data with developers who created games and quizzes for the platform violated Canadian privacy laws.
Facebook announced changes to its privacy settings across the globe as part of a settlement with the Canadian privacy watchdog that required Facebook apps to get explicit consent from users to access their information and allowed users' friends to block access to applications that also requested their data.
In 2011, Facebook also settled an investigation with the Federal Trade Commission over the company's Instant Personalization features, which shared information from users' profiles with external websites so that companies could serve personalized ads and other content outside of Facebook.