Police say a Lone Wolf bikie gang member who was fatally shot in Sydney's south yesterday had assaulted his killer just before the man opened fire.

The killer remains on the run, with police expressing their frustration at a lack of cooperation from witnesses.

Neal Todorovski, 37, was shot in the head, hand and body outside an apartment block at Sans Souci around midday yesterday.

His attacker escaped in a black Land Rover four-wheel drive with New South Wales registration GB-84-AO.

Reports yesterday said there were three men in the car as it drove off.

Two men who were with Mr Todorovski escaped unharmed but were then charged by police.

John Leger, 32, and 23-year-old Matthew Lewis faced Parramatta Local Court today charged with concealing a serious indictable offence and affray.

Leger is also charged with possessing a prohibited weapon.

In police facts tendered the court heard the men were with Mr Todorovski before and during the incident.

Police say before the shooting the three Lone Wolf gang members armed themselves with a pistol, plastic knuckle dusters and a knife before assaulting an unknown man who was parked outside Mr Todorovski's apartment block.

The unknown man managed to free himself from the scuffle and retrieve a gun from the car.

Police say he shot Mr Todorovski and also fired four or five shots at Leger as he chased him down a laneway.

Leger and Lewis did not apply for bail in court today, and will remain in custody until they face court again next week.

Homicide detectives have formed Strike Force Lobbe to investigate the killing.

Detective Superintendent Michael Willing says the lack of cooperation has been frustrating.

"There are witnesses who can provide us information, there are certainly people out there who know who was involved in this shooting and we're asking people to come forward with information that could help us," he said.

"There is no honour in remaining silent when it puts the lives of the community, other members of your family and other people that you may know at risk.

"We would appeal for those people to seek what is the right thing to do, which is to come forward and give us that information so that we can ensure the safety of the whole of the community."

Earlier police said their investigation would include possible links to a series of recent violent incidents linked to the Lone Wolf gang.

A member's teenage son was stabbed to death in Sydney's west last month, while the Lone Wolf clubhouse was torched in September.

There have been suggestions of a turf war being fought between the Lone Wolf and Rebels bikie gangs.

Detectives were also examining possible links to the stabbing of a 25-year-old man in nearby Brighton-Le-Sands on Tuesday.