Mourners wearing hoodies and face masks carried Hamze's bright green coffin into Lakemba mosque on Wednesday morning amid a strong police presence.

The 34-year-old was sprayed with bullets on Thursday night, opposite the Australian stock exchange, as he left an upmarket Japanese restaurant in what police described as a "brutal execution-style murder".

He was rushed to St Vincent's Hospital, where he died.

The ceremonial preparation of Hamze's body was undertaken before the coffin was taken into the mosque for Salat al-Janazah, the Islamic funeral prayer.

A police strike force is investigating whether the murder is related to ongoing tensions between the rival Hamzy and Alameddines families.

Hamze's mother Maha, who was shot in her legs in 2013 and whose home was again sprayed with bullets in February, attended the funeral.

Ahmed Elomar, the brother of slain Australian ISIS jihadist Mohamed Elomar, also attended the service.

Hamze's cousin and founder of the Brothers For Life gang Bassam Hamzy remains in Goulburn Supermax prison, where he has spent most of his adult life for murder and drug-related convictions.

Hamzy's brother Mejid died in the driveway of his southwestern Sydney home last October after he was shot by two balaclava-clad gunmen.

Hamze will be buried at Rookwood cemetery.

Australian Associated Press