Neither this nor any other of Russia's most famous contract killings has been solved.

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In 2010 it emerged that guards at a jail in Durango had allowed prisoners out at night to commit contract killings.

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The Bulgarian government did sack one of its most controversial figures in April: Rumen Petkov, an interior minister known to have had meetings with organised-crime bosses (he insists that he was trying to stop the contract killings).

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Dr Fiona Brookman, a reader in criminology at the University of Glamorgan and deputy director of its Centre for Criminology , told BBC Wales less than 0.5% of recorded murders in the UK were contract killings, according to the available evidence.

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The music is tranquil, the pacing is whatever I want it to be, I can collect and horde, I can be a thief or assassin (all my killings are assassinations because I am of the Dark Brotherhood be it contract or not).

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