Man arrested as 82-year-old fights for life after suspected stabbing in Sydney

An 82-year-old man is fighting for life and a younger man believed to know him has been arrested following a suspected stabbing in Sydney's inner west.

Police were called to Lyons Road near Williams Road in Five Dock about 3:45pm today following reports of a stabbing.

Witnesses said the 82-year-old was stabbed on the street by another man, who ran from the scene.

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They rushed to help the older man before paramedics arrived and rushed him to the Royal Prince Alfred Hospital in a critical condition.

Police, who set up a crime scene in Five Dock, arrested a 51-year-old man in Pyrmont about 6:20pm.

He was tonight assisting police with their inquiries at Day Street police station.

Police said it was believed the men knew each other.

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