Teenager stabbed to death at Sydney bus terminal in 'callous, vicious' attack

Police are investigating whether the stabbing death of a young man in western Sydney was gang-related.

Emergency services were called to a bus interchange on North Parade at Mount Druitt about 10pm yesterday.

Police found two 19-year-old men with stab wounds.

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Zach McCrae was treated by paramedics but died shortly after.

Vimlesh Chand had been stabbed in his arm and chest. He was treated at the scene before being taken to hospital in a stable condition.

NSW Police Superintendent Darrin Batchelor said the attack was violent.

"I describe the attack as callous, vicious and without regard to the victims or innocent bystanders," he said this morning.

"It was quite a violent and frenzied attack on those individuals."

McCrae suffered stab wounds to his chest and was treated by paramedics at the scene, but he could not be saved.

Batchelor said Chand was "extremely lucky" to survive.

"He sustained a stab wound through his arm, went through the entirety of his arm and then penetrated his chest," he said.

Both McCrae and Chand were known to police, Batchelor said. He would not confirm whether the attack was targeted or planned.

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A third person was also assaulted in the incident, but he isn't believed to be an associate of the victims and was simply in the vicinity of the crime.

A crime scene has been established and officers, including the State Crime Command's Homicide Squad, are investigating the death.

Police paused train services in the area to search the tracks for evidence.

It is believed four individuals were involved in the attack, two of whom were armed with kitchen knives.

Batchelor confirmed the four were dressed in black and wearing balaclavas.

There are reports the crime could be gang-related, with the victims reportedly asked if they were "67", an alleged gang in western Sydney.

Police are exploring that line of inquiry, but efforts so far are hindered by the second victim being under sedation in hospital.

A stolen bumbag has made robbery another potential motive.

Anyone with information can contact Crime Stoppers on 1800 333 000.

A report will be prepared for the coroner.

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