Appeal over Hamzy father, son murder

Police are appealing for information about the gangland execution of a father and son in Sydney's west last year.

Salim Hamzy, 18, and his father Toufik Hamzy, 64, were shot dead as they sat parked in a ute at Guildford at 9am on October 20.

Strike Force Ormerod was established to investigate the killings amid speculation the men were victims of the tit-for-tat gangland war between the Hamzy and Alameddine crime networks in their battle over drugs.

Investigators have since seized two cars - a grey Ford Mustang and a burnt-out Lexus SUV - both believed to have been used as getaway vehicles in the murder.

Police revealed on Tuesday that two people have been charged with offences related to Strike Force Ormerod.

A 25-year-old man, Ali Mahfoud, was charged last month with accessory after the fact to murder and refused bail.

He is due to face court again at Parramatta for a committal hearing on September 8.

Police allege he is responsible for moving and storing vehicles used in the double murder.

Detectives also charged a teenager last month after seizing a gel blaster from a Merrylands West home.

A 17-year-old boy was charged with possessing an unauthorised prohibited firearm, not keeping a firearm safely and possessing an unregistered firearm.

He will appear at a children's court on September 30.

Homicide Squad commander Danny Doherty appealed to anyone who may have seen the distinctive grey Ford Mustang or Lexus SUV prior to the murders.

"Following our last public appeal, detectives have since charged a man with accessory after the fact - this will not be the last arrest," Detective Superintendent Doherty said.