Australia's biggest city, Sydney, has been shrouded in red dust blown in by winds from the deserts of the outback.

澳大利亚最大的城市，悉尼，被内陆沙漠吹来的红色尘土大风所掩盖。

Visibility is so bad that international flights have been diverted and harbour ferry traffic disrupted.

Emergency services reported a surge in calls from people suffering breathing problems. Children and the elderly have been told to stay indoors.

Sydney's landmarks, including the Opera House, have been obscured（湮）, and many residents are wearing masks.

Traffic has been bumper-to-bumper on major roads.

The dust blanketing eastern parts of New South Wales has been carried by powerful winds that snatched up（抓起） tons of topsoil from the drought-ravaged west of the state.

One Sydney resident told the Associated Press news agency: "The colour was amazing... I'm 72 years old and I've never seen that in my life before."

The Australian Bureau of Meteorology warned of "widespread damaging winds" in Sydney and other areas, as gusts of 65km/h (40mph) hit the city.

Forecasters predicted the winds would weaken later on Wednesday.

The BBC's Phil Mercer in Sydney says it has been a difficult 24 hours for Australia, which has been hit by earthquakes, hail storms and bushfires.

In parts of New South Wales, huge hail stones whipped up by thunderstorms smashed windows and sent residents running for cover.

Further north in Queensland, officials banned open fires in many areas when bushfires sprang up after a spell of hot, dry weather.

Two minor earthquakes hit Victoria state on Tuesday, and heavy rains that followed led officials to issue a warning of flash floods.