Journalists Steven Sotloff (left) and James Foley (right) have both been killed by Islamist militants in recent weeks. Sotloff was pictured in the video delivering message taunting U.S. President Barack Obama. The Arabic text at the bottom of this frame translates to: 'Now is the time for my message'. A knife-wielding jihadist stands next to U.S. journalist Steven Sotloff in the video that was released online overnight. U.S. journalist Steven Sotloff, 31, (left) was kidnapped in Syria last year. Sotloff's mother Shirley (right) made a televised appeal for the return of her son last week. Australian Warren Rodwell, pictured in a ransom video with his Abu Sayyaf captors in the Philippines. Mr Rodwell has today shed light on what it is like to be a captive who has lost hope. He spent 472 days in captivity. He was never tortured and has previously described his abductors as 'buffoons'
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Islamic State militants have murdered two U.S. journalists in the past month
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James Foley and Steven Sotloff condemned America, believed to have been under heavy coercion
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Psychologists and an Australian kidnapping victim explains what life is like in captivity after all hope is lost
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'Nothing really has meaning to you anymore... Someone tells you "say this" and you say it'
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'You just imagine whoever is watching it is smart enough to realise you haven't really got your heart in it'
Freelance journalist @placeholder was executed by the Islamic State on August 19.