A man has been charged with attempted murder after a police officer was stabbed in the leg with a sword in Sydney’s south-west on Friday.

Police were called to a home on Werombi Road, Grasmere, about 5.20pm after reports of a concern for welfare and a breached Apprehended Violence Order.

Officers from Camden Police Area Command tried to arrest a 20-year-old man who allegedly threw a spear at officers before stabbing a 23-year-old probationary constable in the leg with a sword.

Police tasered the man before arresting him and taking him to Campbelltown Police Station.

The man was then taken to Campbelltown Hospital for treatment.

The injured officer was treated by NSW Ambulance paramedics and then taken to Liverpool Hospital in a serious but stable condition where he is awaiting surgery.

A helicopter takes off from a field

The injured officer was airlifted to Liverpool Hospital. (Supplied)

Actions of officers praised

Superintendent Paul Condon, Camden Police Area Commander, said the officer suffered a 20-centimetre laceration and two tourniquets were used to stem the bleeding.

Superintendent Condon praised the actions of the officers.

“I’d like to commend the bravery of my officers and the courage of my officers at the time at a violent situation that could have had a very different outcome, a very tragic outcome if not for their actions,” he said.

“Police are confronted day-in, day-out by violent situations like this.”

Superintendent Condon said the situation “escalated very quickly” and the injured officer was “very junior”.

He said he had seen body-worn footage from the scene, calling it “extremely confronting”.

He said officers seized a number of weapons at the scene, including a spear, hatchet and a 50-centimetre sword.

The man was charged with 11 offences, including two counts of attempted murder.

He was refused bail to appear before Parramatta Local Court on Sunday.