BRUSSELS - EU lawmakers will investigate whether the data of more than 50 million Facebook users has been misused, the head of European Parliament said on Monday.

Antonio Tajani urged the social media giant to take more responsibility, saying on Twitter that "allegations of misuse of Facebook user data is an unacceptable violation of our citizens' privacy rights."

Data analytics firm Cambridge Analytica harvested private information from more than 50 million Facebook users in developing techniques to support President Donald Trump's 2016 election campaign, the New York Times and London's Observer reported on Saturday.