Police say they dismantled a cell of a major criminal gang as part of an investigation triggered by the public shooting of three people on July 23 at Greenacre in Sydney's southwest.
A 25-year-old man was found injured in a parked car after the shooting, while a 22-year-old man and a 19-year-old woman were wounded in a separate vehicle.
The victims' cars, a Toyota sedan and Mazda hatchback, were parked about 50m apart when they were sprayed with bullets.
The older man died in hospital four days later, while the younger man suffered life-changing spinal injuries.
Detectives quickly determined the killing was tied to the Haouchar crime gang, but all three victims were accidentally targeted in a case of mistaken identity.
Eight people were arrested in simultaneous dawn raids across Sydney and the Central Coast on Wednesday.
Among them is a 24-year-old man arrested in Drummoyne who is expected to be charged with murder for his alleged involvement in the shooting.
Two men, aged 25 and 39, were taken from Parklea Correctional Centre and arrested at a local police station ahead of anticipated murder charges.
Several others are likely to be charged with being involved in the criminal group, while a 27-year-old taken from a Wellington prison is expected to be charged with being an accessory before the fact of the murder.
Police say they are yet to find the person who pulled the trigger.
NSW State Crime Command director Jason Weinstein said the Greenacre attack was the worst calibre of crime.
"This criminal group were of the mistaken belief they could do what they wanted when they wanted and showed a blatant disregard for human life in carrying out such a brazen attack on innocent people," he said.