Meet Abu Hajjar, the most senior leader of the so-called Islamic State ever to talk on camera. According Iraqi police, he was their head of finance in Iraq until his capture last year. He tells Peter Taylor they raise money by "taxing" businesses - threatening to kill those who don't pay "with a grenade". For the full immersive experience of this story pls click here http://www.bbc.co.uk/taster/projects/state-of-terror Subscribe to BBC News HERE http://bit.ly/1rbfUog Check out our website: http://www.bbc.com/news Facebook: http://www.facebook.com/bbcworldnews Twitter: http://www.twitter.com/bbcworld Instagram: http://instagram.com/bbcnews