Israel opens investigation into Facebook over Cambridge Analytica It said it would investigate if Israelis' personal data was used illegally.

Israel's privacy regulatory authority announced Thursday that it has opened an investigation into Facebook's activities, following reports that the data mining firm Cambridge Analytica had misused information from up to 50 million Facebook accounts.

Israel's Privacy Protection Authority, which regulates personal digital information, said it had launched the probe into the tech giant in response to reports “on the transfers of personal data from Facebook to Cambridge Analytica, and the possibility of other infringements of the privacy law regarding Israelis."

It said it would “investigate whether personal data of Israeli citizens was illegally used in a way that infringes upon their right to privacy” and Israeli privacy protection law.

The regulatory authority said it had informed Facebook of the move today.

The Privacy Protection Authority noted that, according to Israeli law, "personal data may only be used to the purpose for which it was given, with the consent of the individual."

Facebook did not immediately respond to a request for comment from ABC News.

ABC News' Jordana Miller reported from Jerusalem.