Greenpeace protesters, attempting to board an oil rig in the Arctic run by Russian oil giant Gazprom, said they were threatened by armed guards from the Russian coast guard.
Greenpeace said shots were fired at activists as they attempted to reach the rig.
Video footage of the event, which happened early morning on September 18, shows the activists attempting to mount the rig, and promptly retreating after appealing to the Russian authorities to put down their guns.
Six Brits are among 25 protesters being held by Russian authorities after guards boarded Greenpeace's ship yesterday.
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