Inside is a couch, a Viking helmet, a water gun and a dartboard for workday breaks.

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He then told the inquest how negotiators encouraged Moat to give himself up, and he took up the offer of a sandwich and a bottle of water, but kept the gun pointing at his own head.

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However there has long been a quest for "smoking gun" evidence for liquid water currently on the planet.

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In 1990 an equivalent gun would have used 15 times as much compressed air as water, and thus been far more expensive to run.

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Cities are costly where United Nations staff, diamond traders, aid workers, diplomats, mercenaries and gun-runners compete for the few available hotel rooms, bottles of water and reliable taxis.

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