Investigator says several activists will face charges of resisting law officers, in addition to hooliganism charges

Russia will bring more charges against several Greenpeace activists who were arrested for a protest at an Arctic oil rig, investigators have said.

Russia has drawn international criticism over the arrest and subsequent treatment of the 30 people on board the Greenpeace ship Arctic Sunrise when activists tried to scale the Gazprom-owned Prirazlomnaya oil platform.

All 30 were initially charged with piracy, which carries a maximum 15-year sentence, but last month the charges were changed to hooliganism, which carries seven years.

But Vladimir Markin, a spokesman for the investigative team, said some of the activists would also face charges of resisting law officers, which carries a maximum five-year term.

"A few boats approached the platform, and with the aid of special equipment, they tried to climb up the platform. They completely ignored the authorities' orders. Furthermore, if you recall, they rammed the coastguard ship," Markin said in an interview on the news site gazeta.ru.

Greenpeace has always said its protest was entirely peaceful.

Markin's comments came after David Cameron gave an interview on Thursday urging Russia's president, Vladimir Putin, to help free the activists, saying the action taken against them was excessive.

Cameron said he welcomed the decision to reduce the charges to hooliganism, but still felt the action went too far.

"They are not hooligans, they are protesters," Cameron told BBC local radio.

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