SYDNEY — A number of elderly people were killed Friday and many more injured when a fire ripped through a nursing home in western Sydney, emergency services said.

Up to 90 firefighters, a large number of police and paramedics raced to the Quakers Hill Nursing Home in the early hours of the morning when an automatic fire alarm went off to find a scene they said was "chaotic and tragic".

"This has been a very, very serious fire, a tragic scene - a lot of people injured. There have been some fatalities, there may be more," Fire and Rescue NSW Commissioner Greg Mullins told reporters.

The Australian Broadcasting Corporation said up to nine people died while Sky News cited police as saying "fewer than 10" with others rushed to hospital suffering smoke inhalation or burns.

"This is a firefighter's worst nightmare," Mullins added.

"Crews had to literally crawl on their hands and knees into every room in the complex, reach up under the beds, searching cupboards, anywhere where someone may have crawled away."

Around 100 people were evacuated from the building.

Television pictures showed dozens of elderly people lying on beds or sitting in wheelchairs outside the home, some of them being attended to by paramedics.