Fighting the Islamic State group online
When the Islamic State group took over Mosul in Iraq in 2014 it flooded the internet with jihadist propaganda.
One historian living in the city decided to launch a counter-narrative online.
Omar Mohammed set up "Mosul Eye" to expose the atrocities and failings of IS fighters, but at great personal risk.
Omar tells Witness History how he posted news from Mosul to the outside world from right under the noses of IS.
He says it was his duty to tell the real story.
Witness History: The stories of our times told by the people who were there.