Mark Zuckerberg is slated to address a weekly Q&A session with employees on Friday. (File)

Sheryl Sandberg has not yet spoken about the data scandal. (File)

With Facebook getting mired in its biggest-ever controversy following a massive data breach, everyone is asking one question: Where is its CEO Mark Zuckerberg Not only has Mr Zuckerberg remained quiet so far, Facebook COO Sheryl Sandberg, who has been the face of the company's PR strategy, is yet to speak on the data scandal.According to a report in ReCode on Wednesday, Mr Zuckerberg is slated to address a weekly Q&A session with employees on Friday and he may speak before that meeting.Normally, Mr Zuckerberg or Ms Sandberg come out with long blog posts whenever Facebook gets tangled in controversies but the silence this time is deafening.Facebook is facing the heat after Cambridge Analytica, a British consulting company, was accused of harvesting data of up to 50 million Facebook users without permission and using the data to help politicians, including US President Donald Trump and the Brexit campaign.European Union (EU) and British lawmakers have demanded that social media giant Facebook should clarify data breach following revelations that personal data was massively misused for political purposes.British lawmakers have also summoned Mr Zuckerberg to give oral evidence after "misleading to the Committee" occurred at a previous hearing.British Prime Minister Theresa May has expressed her concern over the allegations that Cambridge Analytica exploited data of millions of Facebook users without their authorisation in election campaigns.Facebook has already suspended Cambridge Analytica from its platform.

The social media giant admitted that an estimated 2,70,000 people had downloaded the app and shared their personal information with it.However, the firm denied all wrongdoings and insisted it followed the correct procedures in obtaining and using data.