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A massive manhunt was last night under way for an axe-murderer who hacked to death a woman and two children and seriously injured an off-duty policewoman, in a New South Wales country town.
A third child is reported to have been at school and to have escaped the killings.
Police want to question John Walsh, 69, believed to be the children's grandfather.
They locked down a house in Cowra as a helicopter flew the injured woman to hospital in Orange, in the state's central west, and began a sweep for a silver Toyota Avalon driven by a man feared to be armed and dangerous.
Police said the suspect, the father of injured Senior Constable Shelley Walsh, could be headed through the Blue Mountains for the coastal city of Newcastle, north of Sydney.
They fear he could be planning another killing there.
The murders at Cowra, a small town west of Sydney known for the wartime massacre of Japanese prisoners attempting a mass escape, follow the shocking deaths of three young children in a murder-suicide on the NSW south coast last week.
Gary Bell, 44, gassed himself and his children, Jack, 7, Maddie, 5, and Bon, 18 months, in a 4WD, despite an apprehended violence order against him and reports passed to the NSW Department of Community Services.
Premier Morris Iemma has ordered an investigation.
In Cowra yesterday, police were called to a house in Brougham Street shortly after 2pm, apparently after a woman believed to be an off-duty police officer, staggered to a neighbour's home.
Terry Lovett told news.com.au that the mother of the two dead children, a boy aged 7 and a girl aged 5, had been bleeding from the head and had to be helped inside by his wife, Cheryl.
"Apparently she came in screaming that her father's gone off and axed the kids," he said.
The injured woman was reported to be estranged from her husband, and the Sydney Morning Herald website said the murdered woman was her mother.
Cowra Bowling Club barman Chris Milburn told the site that armed police with guns drawn had swarmed around the house.
Police have appealed for help in finding a Toyota.
