A police officer has been killed in a suspected axe attack in Sydney's northwest while responding to a domestic dispute.
The male officer was part of a police response to a reported dispute between two neighbours at a rural property in Oakville, about 2pm (AEST) this afternoon.
Paramedics were called to the scene about 4.15pm and treated the injured officer, before he was taken to Hawkesbury Hospital, where he died.
Media reports say two people have been arrested, and the Seven network says one of the people involved could have been carrying a bow and arrow.
It is 252nd death of police officer on duty in New South Wales since records began.
A male suspect in his 20s has been arrested, the Seven Network reported.
Other media reports indicate two men had been taken into custody and were being questioned by police.
Media footage has shown a shirtless man being handcuffed as he lay on the ground.
The fatally injured officer, a senior detective aged 45, was described to Fairfax Media as 'very experienced'.
The Nine Network has reported that the officer was well known and very popular in the local area.
Mr Scipione spoke briefly to media outside the hospital to confirm the officer was a 45-year-old detective-inspector with a wife and child.
The police commissioner was at the hospital with the family of the slain officer.
His parents were on their way to the hospital, according to media reports.