Two people are now dead after a stabbing in north-west Sydney this morning.

Just before 5am, emergency services were called to a home in Illabo Street in Quakers Hill after reports of a disturbance.

Police found a man, believed to be in his 30s, on the footpath who had suffered apparent stab wounds.

A woman was found dead inside the home. She is yet to be formally identified but is believed to be aged in her 30s.

The injured man was taken to hospital in a critical condition, but police said later this morning that he had since died.

Police arrested a 47-year-old man after he attended Blacktown Police Station at about 5.30am.

The investigation continues.

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