The seizures came as south-western Sydney brothers Ezzeddine Omar, 38, and Mohammed Omar, 44, were charged in connection with the killing, including a charge of murder for alleged getaway driver Ezzedine.

Mejid, 44, brother of the jailed Brothers 4 Life gang leader Bassam Hamzy, was gunned down outside his Simmat Avenue, Condell Park home on October 19 last year, sparking an escalation in an ongoing gangland war.

On Wednesday morning police raided addresses in Liverpool, Peakhurst, Bringelly and on Walker St, Helensburgh. About 20 officers blitzed the Illawarra address, including several Strike Force Raptor police.

Attention focused on several outbuildings and a large shed, where the police seized three vehicles including a Holden Maloo ute, a white BMW-486 and a silver Porsche.

Meantime, two men since identified by the ABC as the Omar brothers were arrested at their Liverpool and Croyden homes.

Police will allege Ezzeddine Omar, now charged with a suite of offences including murder, proceeds of crime offences and car rebirthing, is an associate of the Alameddines, a rival family to the Hamzys.

Detective Acting Superintendent Grant Taylor said police would allege he was involved "before, during and after the murder of Mejid Hamzy".

"We'll allege that [Ezzeddine Omar] was the driver of one the vehicles in the getaway after the murder ... it is not alleged that he's the actual shooter of Mr Hamzy. We are still obviously looking for more people involved in this matter."

The elder Omar is charged with hiding a white BMW allegedly used as a getaway car.

Supt Taylor said Wednesday's searches were focused on finding evidence "in relation to the shooting murder as well as a number of other offences".

"We've found numerous bits of stolen property at these locations and we're identifying whether those vehicles, one of which was [a Porsche] stolen from Hunters Hill, has been involved in any other crimes."

"There's tentacles everywhere in this job in regards to criminality ... these two individuals we believe are known to other persons that are of interest to us."

Bassam Hamzy was initially jailed for 21 years for shooting a teenager dead in 1999, when he was 19.

He started the Brothers 4 Life gang while in jail, after converting to radical Islam. The gang was borne out of internal disputes between a Lebanese Australian Bankstown chapter and an Afghan Australian Blacktown chapter, and has built a history steeped in violence and death.

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On June 17 Bassam's cousin, Sydney crime boss Bilal Hamze, 34, was shot dead as he departed a Bridge Street Sydney restaurant. Hamze had spent the last months of his life with a bounty on his head and had been warned by detectives they were concerned about an ongoing feud with the Alameddines.

State Crime Commander, Acting Assistant Commissioner Darren Bennett, said Wednesday's arrests were the result of nearly 10 months of investigations by Strike Force Courier detectives.

"Since October last year, investigators have reviewed hours of CCTV vision and spoken to numerous witnesses to ensure those responsible are charged and put before the courts," he said. Strike Force Courier's investigations are ongoing.

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