#BBCtrending: Mapping Islamic State followers around the world
20 June 2014 Last updated at 18:50 BST
The Sunni militants of Islamic State aren't just taking over territory in Iraq - they're also trying to advance into people's social media timelines.
Islamic State is spreading violent videos and propaganda messages using hashtags and even its own smartphone app - which was later removed after an investigative report about it.
The BBC Trending team have mapped IS social media posts across the world. They tell a revealing story about the group's strategy and support.
Video journalist: Benjamin Zand
Presenter: Mukul Devichand
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