Girgory Pasko struck on head in Siberian city after arriving to hold seminar for local reporters and bloggers.
'Don't forget about your own safety while searching for beautiful pictures,' residents and visitors are warned. Picture: Petrozavodsk Govorit
The well-known journalist - previously jailed under espionage laws for exposing radioactive pollution by the navy - said he was attacked by two burly men outside his hotel in Barnaul, capital of the Altai region.
One of them one 'hit me very hard on the temple', he alleged. They shouted at him: 'Get out of our city - we'll get you!' said Pasko, the director of Foundation 19/29 that supports investigative journalists.
He claimed the attack happened a day after a local news site reported his arrival, calling him a traitor and a spy, and threatening to follow and film his every move while he was in Barnaul. He reported the attack to local police.
The Russian Union of Journalists said it was 'concerned by what happened to Grigory Pasko and will follow how the situation develops'.
Pasko also said that local police had arrived prior to his training session and recorded all participants' passport details on the pretext of 'checking for migrants'.
He said: 'We have never had such checks before, not since we started our training in 2009.' The case was highlighted by the New York-based Committee to Protect Journalists.
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