A man has been hospitalised after he was shot by police while allegedly rushing at officers with a knife at a caravan park.
Emergency services attended the caravan park in Sydney's southwest about 12.15pm on Thursday for a welfare check.
Officers tried to speak to a 52-year-old man in a cabin at the Elderslie property.
He had armed himself with a knife and made threats to self-harm, NSW Police said in a statement.
Tactical police attended as negotiators tried to speak to the man.
The man allegedly rushed at police with the knife when officers entered the cabin about 3.30pm.
A taser and "less than lethal" tactical rounds were ineffective and the man was shot, police said.
He was treated by paramedics on the scene before being taken to Liverpool Hospital in a critical condition.
Assistant Commissioner Brett McFadden told reporters officers had been forced to protect themselves while trying to save the man from harming himself.
A critical incident has been declared to investigate the police-involved shooting.
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