A few moments ago, fifty polar bears entered and occupied Cairn Energy's headquarters in Edinburgh, England. Their purpose? To look for Cairn's elusive Arctic oil spill response plan, and to take your messages to the heart of the company.

The fragile world of the Arctic - home to the Polar bear, the Narwhal whale and scores of other species found nowhere else on Earth, as well as to four million humans who rely on the unique balance of nature for their economy and survival - is under threat.

As the ice melts, oil companies are moving in to extract more of the fossil fuels that caused the melt in the first place. Cairn is spearheading this new oil rush at the top of the world, drilling in sites that are as deep as the Macondo well that ruptured in the Gulf of Mexico.

But above the Arctic circle, freezing temperatures, a narrow operational window and a remote location mean that a spill would be almost impossible to deal with. It's a catastrophe waiting to happen.

We're asking Cairn to publish its oil spill response plan.

More than 50,000 of you have already asked them to do so, including the global head of Greenpeace who boarded an Arctic rig to ask for it. Even the Amsterdam judge presiding over Cairn's lawsuit against Greenpeace questioned why Cairn didn't publish its plan.

Cairn's response? Nothing. Public scrutiny would show that an Arctic spill would be near impossible to clean up and that Cairn is woefully ill-prepared. So we are now inside the heart of the company's operations to look for the plan.

Greenpeace UK is on standby, waiting to receive your messages for Cairn. The last time they asked people to contact Cairn, the oil company blocked all emails coming from our system. So this time, we're going low-tech, with pens and Post-It notes, and putting the messages where Cairn can't fail to see them: on their computer monitors, their desks, their notice boards and their office walls.

Each message you send us will be hand written - by a polar bear - so please keep it short, for the sake of the bears.

Post a message in the comments on the Greenpeace UK blog tweet with the hashtag #Cairn, or comment on the Greenpeace UK Facebook posts.

The bears will also, of course, be updating us throughout their occupation, so keep coming back to check the live updates.

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