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German Chancellor Angela Merkel was overheard confronting Facebook CEO Mark Zuckerberg over incendiary posts on the social network, Bloomberg reported on Sunday, amid complaints from her government about anti-immigrant posts in the midst of Europe's refugee crisis.

On the sidelines of a United Nations luncheon on Saturday, Merkel was caught on a hot mic pressing Zuckerberg about social media posts about the wave of Syrian refugees entering Germany, the publication reported.