After almost a year spent in Lebanon, a tracksuit-clad Ahmad stepped off a flight at Sydney International Airport on Monday night and into handcuffs.

Homicide detectives were waiting for the bulky character after receiving a tip-off about his long-speculated arrival.

It has been a major breakthrough for police, who are investigating five shootings potentially linked to the same dispute between well-known families in Sydney's south-west.

Hours after emerging from his Qatar Airways flight, Ahmad was charged with the murder of Safwan Charbaji in Condell Park last year.

Ahmad, the brother of slain standover man Walid "Wally" Ahmad, did not appear in Waverley Local Court on Tuesday when his case was briefly mentioned.

Investigators had been waiting for the 34-year-old underworld figure to return home ever since April 30 last year, when they issued a warrant for his arrest for murder.

Three weeks earlier, Ahmad was allegedly one of several men involved in a violent confrontation outside A Team Smash Repairs in Condell Park.

While investigators believe more than one gun was pulled by figures on warring sides on that April 9 afternoon, it will be alleged Ahmad fired the shot that killed Mr Charbaji.

It is understood CCTV seized from one of the many industrial businesses on Ilma Street captured a man, who police allege was Ahmad, fire towards Charbaji as he tried to leave.

Charbaji was related by marriage to the rival Elmir family.

Members of the family, including Fawaz Elmir and son Stephen, turned up at the smash repairs business, run by Wally Ahmad, that day to settle a dispute with the Ahmads.

It will be alleged one of the grievances aired involved a disagreement over a $100,000 debt.

Abdullah El Masri, who used to work for Wally, ended up with a bullet to the jaw but survived.

Mr Charbaji was shot in the head and chest. His relative and friend Adam Abboud drove him to Bankstown Hospital.

When police opened the passenger side door of the car Mr Charbaji was travelling in, a number of spent bullets tumbled out of the lifeless figure's lap, documents previously tendered in court showed.

The relative, who can't be identified, and Abboud were later charged with concealing a serious indictable offence, with police alleging they withheld critical information about the shooting.

However those charges were dropped.

A warrant for the arrest of Mr Charbaji's uncle Fawaz Elmir, 48, was issued in the weeks after the shooting but police have not been able to find him.

In the days after the Condell Park melee, as police tried to piece together who shot at who and why, Brownie Ahmad left the country for Lebanon.

He went on to spend the next 10 months there but was in communication with his lawyer back home about the Condell Park allegations, it is understood.

Ahmad was overseas when his older brother, Wally, was killed in a brazen daylight execution at Bankstown Central on April 29.

The suspect in that shooting, Hamad Assaad, was killed in a similar hit outside his Georges Hall home last October.

It is understood Assaad, who had been investigated for carrying out non-fatal but high-profile shootings in recent years, was doing business with a rival crime family.

Similarly, a suspect in his death was killed in a particularly callous shooting earlier this month.

Kemel "Blackie" Barakat, 29, was in his bed in his Mortlake apartment when a gunmen fired more than a dozen bullets into the Hells Angels bikie gang associate's body.

Mr Barakat was close friends with Ahmad's brother, Ahmad "Rock" Ahmad.

Police are also looking at links between those fatal hits and the shooting of bikie associate Radwan Zraika in Chester Hill on March 1.

Sources say Zraika was good friends with Assaad and was related by marriage to well-known western Sydney family, the Alameddines.