NSW Police has established a crime scene where specialist officers have forensically examined it.
The paramedic's family has requested his name not be made public yet.
NSW Police Deputy Commissioner Mal Lanyon said she was shocked by the attack.
“In order to render assistance to paramedics on the scene, police were forced to use a taser and subsequently arrested that 21-year-old male,” she said.
NSW Ambulance Commissioner Dominic Morgan said this was an “extremely difficult time for his young family”.
“This is very raw, very early and very close to home,” Mr Morgan said.
“I had the privilege of meeting with his mother and father, wife and sister who as you can imagine are beside themselves after this tragic loss,” he said.
Local detectives have commenced an investigation, with assistance from the State Crime Command’s Homicide Squad.
Police urge anyone with information to come forward and contact Crime Stoppers on 1800 333 000.
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