SYDNEY, Australia - Sydney's iconic Opera House and Harbour Bridge have gone black as the first major world city to turn off the lights in this year's Earth Hour.


The lights on the Harbour Bridge turned off at 8 p.m. as part of a global campaign to raise awareness of climate change.

That was followed shortly by the Opera House and other landmarks in the city. Most businesses and homes were already dark, as Sydney residents embraced their second annual Earth Hour.

More than 2 million people and 2,000 businesses marked last year's event, and organizers expected this year to be more widespread in Australia.

The event is also spreading later in the day to hundreds of cities and towns in more than 35 nations, organizers said.

THIS IS A BREAKING NEWS UPDATE. Check back soon for further information. AP's earlier story is below.

SYDNEY, Australia (AP) _ Lights dimmed and flickered out in New Zealand and Fiji on Saturday as the two countries became the first to launch Earth Hour, a global campaign to raise awareness about climate change.

Hundreds of cities and towns in more than 35 nations promised to join them, organizers said.

In Christchurch, New Zealand, more than 100 businesses and thousands of homes were plunged into darkness, computers and televisions were switched off and dinners delayed for the hour from 8 to 9 p.m. Suva, Fiji, in the same time zone, also turned off its lights.

Auckland's Langham Hotel switched from electric lights to candles as it joined the effort to reduce the use of electricity, which creates greenhouse gases that contribute to global warming.

The campaign was later to move to Australia _ where Sydney's iconic Opera House and Harbour Bridge as well as shops and homes would be darkened _ before spreading through Asia, to Europe and then North America.

One of the last major cities to participate will be San Francisco _ home to the soon-to-be dimmed Golden Gate Bridge.

"What's amazing is that it's transcending political boundaries and happening in places like China, Vietnam, Papua New Guinea," said Earth Hour executive director Andy Ridley. "It really seems to have resonated with anybody and everybody."

Organizers see the event as a way to encourage the world to conserve energy. While all lights in participating cities are unlikely to be cut, it is the symbolic darkening of monuments, businesses and individual homes they are most eagerly anticipating.

"Earth Hour is about everyone and every organization, from individuals to global companies, joining together to own a shared problem _ climate change," Ridley said. "The real goal for me is the number of people who take part."

Earth Hour debuted last year in Sydney and a reported 2 million people and 2,000 businesses participated, organizers said. They said the result was a 10.2 percent reduction in the city's greenhouse gas emissions for the hour.

"I hope participants take away the knowledge that everything you do, however small it is, counts," Ridley said.