The group -- dubbed the Arctic 30 -- was arrested by Russian authorities in September after two Greenpeace activists tried to scale the side of an oil rig operated by the Russian energy giant Gazprom, RIA Novosti reported.
Investigators originally charged the group, which is made up of 28 Greenpeace activists from around the world and two journalists, with piracy, but those charges have been downgraded to hooliganism.
Greenpeace said the transfer began at 5 a.m. local time and the Russian Investigative Committee confirmed the move, saying the body investigating the case is based in St. Petersburg.
St. Petersburg is about 650 miles south of Murmansk.
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