Greenpeace ship in Murmansk

Russia's powerful Investigative Committee on Tuesday said a piracy probe had begun against activists on board the captured Greenpeace ice breaker Arctic Sunrise as it was towed into port by Russian tug (the tug is pictured above in a Greenpeace photo taken from the Arctic Sunrise).

Agents of Russia's Federal Security Service had stormed the Arctic Sunrise on Thursday after two activists from Finland and Switzerland climbed onto a Gazprom oil platform in the Pechora Sea, northwest of Russia's Arctic coastline, an area prized for its fisheries and wildlife.

"It should be noted that all persons who attacked the [oil] platform, regardless of their citizenship, will be brought to criminal responsibility," said committee spokesman Vladimir Markin on Tuesday.

Greenpeace rejected the allegations and demanded that its activists be freed. Its branch in Germany said members had protested outside Gazprom offices in Berlin as part of a campaign to stop oil drilling in the Arctic.

A Russian tugboat had towed the Dutch-flagged vessel into Murmansk after its Greenpeace captain refused to steer it while the entire crew remained locked in the mess or dining area.

Seizure 'illegal,' says Greenpeace

The environmental lobby group said Russia's seizure of the ship was illegal because the Arctic Sunrise had been in international waters.

Gazprom said impacts of its Prirazlomnaya platform were being monitored, but Greenpeace said such projects endanger a hugely sensitive environment.

Energy producers are increasingly focusing on the Arctic as global warming breaks up ice flows to reveal access to oil and gas reserves under the seabed.

Climate talks in Stockholm

The seizure of the Arctic Sunrise and its crew coincided on Tuesday with climate talks in Stockholm involving scientists and officials of more than 110 governments.

The Intergovernmental Panel on Climate Change (IPCC) is spending four days drafting a report, arguing for a greater emphasis on renewable energies in a bid to slow down warming.

Leaked versions of the draft say human activities, primarily the burning of fossil fuels, are the main cause of global warming, to within a probability of at least 95 percent.

Most impacts such as sea-level rises are projected to get worse unless governments sharply cut greenhouse gas emissions from combustion.

The IPCC draft report says that, if unchecked, temperatures could rise by up to 4.8 degrees Celsius (8.6 Fahrenheit) this century, while deep emissions cuts could restrain rises to 0.3 degrees Celsius.

Compared to pre-industrial times, governments promised last year to limit temperature gains to 2 degrees Celsius. The text also seeks to explain as a "hiatus" the surprisingly slow pace of global warming over the past 15 years amid increasing greenhouse gas emissions, attributing it to volcanic eruptions and other natural variations like the sun emitting less energy than usual.

The report, by 259 authors from 39 countries, is the first of several due from the IPCC over the next year.

In March 2014, another report will focus on climate change impacts on humans and nature; the other due in April will outline how to reduce climate change.

The three working group reports are to be compiled into an overall synthesis report due in October 2014.

ipj/msh (Reuters, AFP, dpa)