Two Greenpeace activists were arrested after being pried from a giant iPod in front of Apple's headquarters Tuesday during a protest against using dirty energy to power data centers.

The protesters had locked themselves inside an eight-foot (2.4-meter) tall, 10-foot (three-meter) wide survival pod previously used during demonstrations to stop oil drilling in the Arctic.

Greenpeace confirmed the arrests but could not immediately confirm the charges.

The activists were broadcasting recorded messages urging Apple to use clean energy instead of climate change culprit coal for electricity to power online services such as iCloud data storage, according to Greenpeace.

"Apple's executives have thus far ignored the hundreds of thousands of people asking them to use their influence for good by building a cloud powered by renewable energy," said Greenpeace USA executive director Phil Radford.

"As Apple's customers, we love our iPhones and iPads, but we don't want to use an iCloud fueled by the smog of dirty coal pollution."

Apple, however, rejected the Greenpeace findings as outdated or flat-out wrong, and said it was leading the pack when it comes to shifting data centers to clean energy.

The company's new North Carolina data center aims to get more than 60 percent of its power from renewable sources including an on-site solar farm and a fuel cell installation touted as the largest of their kind in the United States.

The facility will be "the greenest data center ever built" and will be joined next year by one in Oregon powered completely by renewable energy, Apple said in response to an AFP inquiry.

The protest began late Monday with activists projecting pictures, Twitter messages and Facebook posts from supporters of a "Clean Our Cloud" campaign onto walls of Apple's headquarters in the California city of Cupertino.

Apple employees arriving for work in the morning were greeted by four protesters wearing iPhone costumes with giant screens displaying similar messages, according to Greenpeace International spokesman David Pomerantz.

"The costumes are pretty hilarious, so I'm seeing a lot of smiles and laughs," Pomerantz said of reactions by arriving Apple workers.

More than 215,000 people have reportedly signed a Clean Our Cloud petition since the campaign launched last month with the release of a report grading major technology firms on the use of renewable energy sources.

Amazon, Apple and Twitter were graded poorly in a Greenpeace study of technology titans' use of clean energy to power the mushrooming Internet cloud, but Facebook, Google and Yahoo! won praise.

The environmental group's report, billed as a rallying cry instead of a critique, related the companies' use of data centers and other energy issues.

Both Amazon and Microsoft data centers rely heavily on "dirty and dangerous coal and nuclear power," according to the report.

Greenpeace called on all technology firms using data centers to provide online software or services to be more open about energy use and to shift to non-polluting sources of power.