The dark night claims 1bn worldwide

Global - Although concrete numbers are still some time off, WWF estimates that approximately 1 billion people around the globe participated in Earth Hour this year.

"Early reports are showing that nearly 1 in 7 people in the world took part, making this an event unlike any other in history," said Andy DiLallo and Jay Benjamin co-executive creative directors at Leo Burnett Sydney, the agency behind the global Vote Earth campaign.

"We could not be happier with the results from this year's Earth Hour."

What started as an event launched by WWF and Fairfax Media in Sydney in 2007 has now spread across the world.

Lights went out over many of the world's most famous icons including the Sydney Opera House, Greece's Parthenon on top of the Acropolis, the Las Vegas strip, New York's Empire State Building, the Eiffel Tower, London's Big Ben, Piccadilly Circus, the statue of Christ in Rio de Janeiro and San Francisco's Golden Gate bridge.

Locally, more than 250 Hong Kong companies including HSBC, Cathay Pacific, Cheung Kong (Holdings) Limited, Sino Group and Sun Hung Kai Properties shut off their lights for one hour on 28 March.

Local landmarks the Bank of China building and IFC Tower have both switched off their lights and the SAR government suspended Hong Kong's nightly light show.

In the Philippines alone over 650 towns and cities took part.  In China thousands of public buildings switched off their lights, including the Bird's Nest stadium.

WWF are now taking the results of the Vote Earth campaign to the Global Climate Change Conference in Copenhagen 2009, urging governments of the world to adopt official policies to take action against global warming.