Facebook CEO Mark Zuckerberg has told US Senators his company is in a constant battle with Russian operators seeking to exploit the social network.

Zuckerberg was answering questions in the wake of the Cambridge Analytica data collection scandal.

He also revealed Robert Mueller, the special counsel investigating alleged Russian meddling in the 2016 election, had interviewed Facebook staff.

Zuckerberg said he has not been among those interviewed by Mueller's office.

Asked about Facebook's role in the allegation against Russia, Zuckerberg said the company was developing new tools to identify fake accounts.

Source: bbc.com