Sky turns orange in Australia, residents are alarmed

Authorities issued a public health warning for Sydney, while the 500km-wide sand mass reached the city and caused delays in flights.

In many other areas of New South Wales, visibility is flawed. Authorities said the storm was caused by strong winds that carried sand from dry lands.

The problem has escalated as a result of the drought affecting the entire New state. South Wales since August.

Emergency teams said that dozens of people have reported respiratory or asthma problems, but the number of affected is not immediately clear. In Sydney, sand darkened the sky and made air quality worse.

Health officials urged residents to stay at home, especially children, the elderly and those with respiratory problems.

“Most people with heart disease and lungs are at risk. So they are advised to stay in closed environments”, said Richard Broome, director of environmental health.

Sydney's sandstorm recalled another event, even more intense, in 2009. At the time, the sandstorm affected hundreds, causing breathing problems and left hundreds of flights on the ground.