SYDNEY, Oct 24 (Reuters) - A plane dousing wildfires in bushland around the Australia's biggest city, Sydney, crashed into a national park on Thursday, sparking a new fire to add to 55 still burning across the state of New South Wales.
The accident happened as the immediate threat from the fires eased thanks to cooler weather, but the Rural Fire Service (RFS) warned of hot and dry weather ahead as summer hits its peak.
"It's hard to definitely say that (the worst is over) at this stage," said RFS spokeswoman Natalie Sanders. "We have got cooler temperatures today and the winds are slightly lower but with these fires still going, it's hard to say how long they'll go for and whether there will be any further damage."
More than 200 homes have been destroyed in New South Wales since last Thursday, when fires tore through Sydney's outskirts, razing entire streets. One man died from a heart attack while trying to save his home.
The RFS said it held "grave concerns" for the pilot of a water bomber fixed-wing aircraft that crashed in the Budawang National Park, 270 km (170 miles) southwest of Sydney, a wilderness area of steep mountainsides and forests popular with hikers and campers.
Sanders said 20 of the 55 fires still burning on Thursday had yet to be contained by firefighters, who fear strong winds may see three major fires in the Blue Mountains commuter district west of Sydney join up in coming days, creating one massive wildfire.
The fires have so far burned through more than 120,000 hectares (300,000 acres) and have a perimeter of some 1,600 km (990 miles).
Police have arrested several children suspected of starting fires. Other fires were sparked by power lines arcing in strong winds, according to the RFS.