Founder of social media giant questioned at hearing amid concerns over company's track record on civil rights, hate speech, privacy and misinformation

Regulators and legislators increasingly wary of social media giant's motives, with its business model regarded as too invasive of users' privacy

Technology developed by subsidiary Calibra will let users 'save, send and spend' Libra, the global currency Facebook is planning to launch in 2020 based on blockchain technology

Reuters: Facebook unveils plans for cryptocurrency in an effort to expand reach beyond social networking to e-commerce and global payments