Russia has moved the crew of a Greenpeace Arctic protest ship from the northern port of Murmansk and put them on a train to St Petersburg, the organisation says.
The 28 activists and two reporters, arrested in September after protesting against oil exploration in the Barents Sea, left their detention centre at 5am local time on Monday and are now on a train, Greenpeace spokeswoman Dannielle Taaffe said.
The arrested crew of the ship Arctic Sunrise includes 26 foreigners from 18 countries, including New Zealand's Jonathan Beauchamp and David Haussman.
They have been held for nearly two months on charges of piracy and hooliganism after an attempt to scale an oil platform operated by Russia's energy giant Gazprom, AFP reports.
Greenpeace said that "persistent rumours" from diplomatic sources indicate that all 30 are being transferred to St Petersburg - a journey of about 1500km.
One of Russia's northernmost cities, Murmansk endures polar nights in the winter, with temperatures often dropping to below minus 30 degrees Celsius.
Several activists in mid-September attempted to scale Gazprom oil platform in the Pechora Sea, part of the Barents Sea, in protest at the firm's exploration in the Arctic.
Russian authorities boarded the ship on 19 September and towed it to Murmansk. Greenpeace says the authorities had no right to detain the Dutch-flagged ship in international waters.
They initially accused the activists of carrying out illegal research, then charged them with piracy. They then changed the piracy charge to hooliganism, an offence that can be punished by a maximum of seven years in prison.
