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PERTH - A man attacked his mother-in-law with a hammer, then forced her to call her daughter so he could attack her with a knife in their Fremantle home.
Police said the man went to his mother-in-law's home in Steinbeck Place, in Spearwood, late last night (WDT) and assaulted her with a hammer.
He then made her call her daughter, his estranged wife.
When she arrived he attacked her with a knife, causing multiple stab wounds, before both women fled the house, police said.
The man contacted police, and officers arrived shortly after 11.15pm (WDT).
A man is being questioned by police, but no charges have yet been laid.
The two women, whose ages are not known, are being treated in hospital for serious injuries.
- AAP