By Helen Collis PUBLISHED: 07:50 EST, 11 September 2013 | UPDATED: 09:31 EST, 11 September 2013 Bulgaria is closing its investigation into one of the most notorious Cold War assassinations - the killing of exiled dissident Georgy Markov with the poisoned tip of an umbrella on London's Waterloo Bridge. Markov, a writer, journalist and opponent of Bulgaria's then communist regime, died on September 11, 1978 after a stranger shot a poisoned pellet into his leg. Prosecutors have failed to identify, arrest or charge anybody for the crime, known as the 'Bulgarian umbrella', and so they announced today that the case would now be closed.
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Bulgarian dissident Georgy Markov died days after being jabbed with a poison-tipped umbrella as he crossed Waterloo Bridge in 1978
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After 35 years, and no suspects, Bulgaria is closing the case on the assassination of the former BBC journalist
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They say information that came to light this year following the release of secret police files has not brought any clarity on the identity of the killer
Bulgarian defector Markov, a broadcaster for the @placeholder overseas Service, was murdered on Sept 11, 1978