A Russian court has sent another eight Greenpeace activists to prison for protesting oil drilling in the Arctic.

Thirty activists, including two journalists, have now been ordered jailed for two months by a court in the Russian city of Murmansk.

No charges have yet been filed against any of the group, who represent 18 nationalities, including Russia, according to the Associated Press.

Russian prosecutors are still deciding whether to charge the activists with piracy — a count that could lead to a steep fine or jail sentence.

Russian President Vladimir Putin has said that they broke international law but were "not pirates," according to the BBC.

One of the jailed activists is Greenpeace International spokesperson Dima Litvinov, an American and Swedish citizen.

More from GlobalPost: Russia accuses Greenpeace of piracy

The arrests occurred on Sept. 18 when the Russian coast guard boarded Greenpeace's ship, Arctic Sunrise. The raid was prompted by activists attempting to board an oil platform owned by the Russian energy giant Gazprom.

The oil rig is the first of its kind in the Russian Arctic.

Greenpeace called the seizure of the Artic Sunrise "the most aggressive and hostile act" against the group since France bombed one of its ships 1985, killing one person.

More from GlobalPost: Russian court detains Greanpeace spokesman