Firefighters in Australia are continuing to fight some of the worst bushfires to hit the country in a decade, preparing for worsening conditions.

In the Blue Mountains west of Sydney, one of the worst-hit regions in fire-ravaged New South Wales state, 300 homes have been either destroyed or damaged by the fire storm that peaked on Thursday, the Rural Fire Service announced on Saturday.

The damage toll is more than double the last count announced on Friday and will continue to rise as assessment teams and police move deeper into the destruction zone in search of survivors and victims.

Homes have been reported destroyed in other regions, but numbers are not yet available.

A 63-year-old man died of a heart attack on Thursday while protecting his home from fire at Lake Munmorah, north of Sydney. At least five others - including three fire fighters - have been treated in hospitals for burns and smoke inhalation, officials said.

Arson investigations

Arson investigators are examining the origins of several of more than 100 fires that have threatened towns surrounding Sydney in recent days.

The Australian military also said it was investigating whether a major blaze was linked to an explosives training exercise.

The bushfires have been extraordinarily intense and extraordinarily early in an annual fire season which peaks during the forthcoming southern hemisphere summer which begins in December.

This year's unusually dry winter and hotter-than-average spring have led to perfect fire conditions.

About 1,500 fire fighters have been back burning to contain blazes since winds and temperatures became milder on Friday. Several roads in fire-affected areas north, west and south of Sydney have been closed.

On Saturday, 83 fires were burning across the state including 19 uncontained blazes.

Rural Fire Service Deputy Commissioner Rob Rogers described Saturday's conditions as a "pause" before higher temperatures and increasing winds were forecast for Sunday.

"It's just calmed down a little bit and obviously we're bracing ourselves for these worsening conditions," Rogers told Australian Broadcasting Corp. radio.

"What we have is a time for the crews to anticipate the weather coming ahead and try and get as much containment as possible and prevent that fire threatening major population centres when we get worse weather," he said.

In February 2009, bushfires killed 173 people and destroyed more than 2,000 homes in Victoria state.

Source: Al Jazeera and agencies