Man fighting for life after stabbing at short-term holiday rental in Sydney's west

A man is fighting for life after a stabbing attack inside a short-term holiday rental in Sydney's west.

Emergency services were called to a unit on Patricia Street in Mays Hill, near Parramatta, just after midnight today.

A man in his 20s had been stabbed in the torso and stumbled 300 metres down the road before his friends called for help.

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"My friend's about to die, my friend's about to die," his friends told emergency services.

A witness told 9News his face was "bloody".

The man was rushed to Westmead Hospital, where he underwent surgery and remains in a critical condition tonight.

Another man around a similar age was found with an arm injury and taken to the same hospital in a stable condition.

He remains under police guard.

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Police declared two crime scenes and shut down Patricia Street.

"We're not even allowed back in the apartment building right now because police telling us there was a stabbing on level three," resident Marcus told 9News.

9News understands that a fight broke out inside an apartment complex while eight people were inside.

The two men are believed to be known to each other.

Investigations are ongoing and police urge anyone with information to come forward.

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