Greenpeace personnel detained in Russia for a protest against Arctic oil drilling are to be formally charged with piracy.
If found guilty, the 30 detainees could face a maximum punishment of 15 years in prison.
"They will be charged... (with) piracy committed by an organised group," the Interfax news agency quoted a law enforcement source as saying on Tuesday.
The source said the 30 detainees will be charged in the northern city of Murmansk on Wednesday.
But a Greenpeace representative says the organisation's legal team has been advised that only two are to be charged on Wednesday and there has been no formal information about what the charges will be.
The Arctic Sunrise was boarded by Russian Coastguard officers on 19 September after Greenpeace members scaled an oil platform in the Barents Sea on 18 September to protest against drilling by Gazprom. The icebreaker was towed to Murmansk.
Those aboard the ship are being held in pre-trial detention centres in the cities of Murmansk and Apatity, nearly 2000km north of Moscow.
All but four are non-Russians. They come Argentina, Australia, Britain, Finland, New Zealand and the United States.