Australian bush fires still rage out of control

At least 75 bush fires are burning out of control around Sydney and across Australia's most populous state.

Fire officials believe most were deliberately lit.

Strong winds continued to fan the flames which have destroyed homes, isolated towns and cut major highways across New South Wales.

Hundreds of extra firefighters from the neighbouring state of Victoria are heading north to join almost 5,000 emergency workers, hundreds of whom have been battling fires for five days.

No fatalities have been reported after five days of increasing numbers of fires, but a fire brigade officer was injured on Christmas Day when a roof collapsed on him and dozens of others have suffered minor injuries.

Dry conditions and, on Christmas Day, winds gusting up to 55mph and temperatures above 95F have left fire crews helpless to contain the flames.

New South Wales fire chief Phil Koperberg said some of the fires had been caused by lightning, but others had been deliberately lit.

Though not as extensive as the devastating blazes of Christmas 1994 when four people were killed as 284 bush fires flared across the state, the winds had propelled the fire fronts at unprecedented speeds.

"We have had what is effectively history-making behaviour," Mr Koperberg said. "We have never seen anything like that before."

Sydney has been left blanketed by brown haze and ringed by fires and strong winds are likely to continue.