A man shot dead outside his Punchbowl home overnight was related to the wife of a man gunned down three weeks ago while he worked on his unfinished family home less than a kilometre away.
Bachir Arja, 28, known as Barry, died in his mother's arms following a targeted execution in Owen Street just before midnight .
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Fatal Shooting in Punchbowl
Police are interviewing witnesses after a 28-year-old man was killed in a shooting at his home in Punchbowl, Sydney late on Tuesday.
His distraught mother, Malake, yelled "don't die, don't die, your fiancee is coming" as relatives tried to revive her son in their front yard.
Sanaa El Arja, whose husband Ali Hachem Eid was shot three times in November as he worked on his family's half-finished mansion in Lumeah Street, Punchbowl, said Mr Arja was her cousin.
She said she was rattled and shocked by the murders of both her husband and her cousin.
"I don't know how, I don't know why, I don't know what all this means," she said on Wednesday morning.
Police said there were no obvious links between the two shootings despite the family relationship.
Mr Arja, who had become engaged two months ago, is believed to have been shot in the head and died at the scene.
A friend told Fairfax Media the victim had been at home, where he lived with his widow mother, Malake Arja, when he received a telephone call to come outside.
Mrs Arja told the friend that she yelled out to him "what's that sound?" and when she received no answer she went outside and saw him lying out the front of the house covered in blood.
Detective Superintendent Michael McLean said the victim was known to police, but there was nothing in the initial investigation to suggest he had any gang affiliations.
"We know that the male was inside the house ... shortly before the incident and something certainly alerted him to go to the front of the property," Superintendent McLean said.
"It's hard to explain, people going crazy killing each other
"Upon leaving the front door of his premises, that male was shot a number of times and unfortunately fatally wounded.
"He was shot when he was entirely outside the front of his house, but certainly within the confines of the property."
Mr Arja's mother was among a number of relatives inside the home at the time of the shooting and police were planning to interview her.
"The family's deeply traumatised by this shooting," Superintendent McLean said.
One of Mr Arja's sisters, who has been comforting her mother all morning, said: "He is a good boy, a humble boy".
One cousin who lives on the same street said she heard eight gunshots.
Witnesses said at least two people were seen running from the home.
A large number of grieving relatives and friends rushed to the street last night, and friends took to Facebook to pay tribute to the 28-year-old.
"Allah yerhamak," said one, which in Arabic means may Allah have mercy on your soul.
"May the eyes of the cowards never sleep," the friend said.
Cousins who have gathered at the scene said Mr Arja loved the water and was always taking his boat and jetski out.
"Whenever the weather was good, he'd be out on the water," said a friend.
His future brother-in-law's boat is still parked out the front of the house.
Mr Arja owned a tobacconist shop in Punchbowl and worked long hours, family members said.
"If you ask a favour of him, he'd always say yes, he's very kind," said one family member.
A woman who lives opposite the house where the shooting occurred said she woke to three bangs, and initially thought it was her Christmas lights popping.
"I heard 'Bang, bang, bang'. I didn't really know what was going on," said the neighbour, who asked not to be identified.
"I thought maybe it was my Christmas lights exploding. Then I heard the mum screaming and crying. People started coming outside, and they said there has been a shooting."
The long-time Punchbowl resident said she often waved to the victim's mother, who would sit out the front of her house, but she did not know the victim.
"It is not a nice thing to happen here. I've lived here for 30 years, and I've never had a problem worrying about anything like this," she said.
"It's hard to explain, people going crazy killing each other."
Superintendent McLean said the shooting was believed to be a targeted attack, and the public should not panic about random shootings.
He said there was nothing initially to suggest the shooting was linked to the shooting of Mr Eid, 38, who was a "cleanskin" with no known criminal history or links, but that would form part of the ongoing investigation.
In that shooting, Mr Eid, a father of four, was doing the tiling work on his, Punchbowl home with an electrician, Mohammed Hanouf, 34, on November 28 when two masked gunmen opened fire on them.
Mr Hanouf, also a father, managed to stumble to the front of the house where he collapsed in front of shocked neighbours. He survived the shooting.
Police also do not believe the latest fatal shooting is linked to separate drive-by shootings in Sydney on Tuesday.
Several rounds of bullets were fired at a home and a car in Cherrybrook in north-west Sydney about 5.30am, police said. Meanwhile, a single gunshot was fired from a vehicle at a home in Milperra just before 2am on Tuesday, police said.
Police also are investigating a report of a shot fired during an argument in Sydney's north on Tuesday night.
A witness said an argument occurred between a group of people in a unit block on Shadforth Street, Mosman about 10.50pm, which moved out onto the street.
A single gun shot was heard before the group fled. Police found no-one injured at the address.