A traffic light shows red as a dust storm blankets the Sydney Harbour Bridge at sunrise September 23, 2009. [Agencies]

SYDNEY: A pall of red dust blown in from the Outback clogged the skies over Sydney on Wednesday, diverting international flights, disrupting ferries and prompting a spike in emergency calls from people suffering breathing difficulties.

No one was reported hurt as a result of the dust storm, but officials closed ferry services for hours on Sydney Harbor because visibility was cut to dangerous levels, and police warned motorists to take extra care on the roads.

Such thick dust is a rarity over Australia's largest city, and came along with whiplashing winds and other uncommon weather conditions across the country's southeast in recent days. Hailstorms have pummeled parts of the country this week, while other parts have been hit with a mini-heatwave.

At least 10 international flights and more domestic flights to Sydney were diverted to other state capitals because of visibility problems caused by the dust, Sydney Airports said. Three flights from neighboring New Zealand were turned back from Sydney and returned home because of the dust, Air New Zealand spokesman Mark Street said.