Mother-of-two missing after fatal WA boat crash kills her friend

One woman has been killed and mother-of-two remains missing after a boating crash south of Perth.

Kylie Bazzo - the mother of West Coast Eagles defender Rhett Bazzo - is still unaccounted for in the Mandurah Estuary after a horror crash late Saturday night.

The 52-year-old was thrown overboard when the boat she was on smashed into a navigation marker.

Bazzo's friend Debbie Burdon was tragically killed, and husband John Burdon seriously injured. Another man was unharmed.

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A witness said they yelled out to the boat, which was moving without navigation lights turned on. They watched as the boat hit a pylon at high speeds.

Locals have helped to search on boats, canoes and on foot along the shoreline.

Acting Superintendent Peter Morrissey told 9News the search would continue, but "at this stage we're probably in a space where we're looking to recover a body".

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