A university student shot dead during a suspected “targeted attack” may not have been the intended target, with police investigating a possible case of mistaken identity.

Marco Tapia, 23, was in bed when intruders stormed his family’s home on Mount Sugarloaf Rd at Glen Alpine, in southwest Sydney, just after 3.30am on Tuesday.

WATCH THE VIDEO ABOVE: Deadly home invasion in Sydney’s southwest

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Police said the biomedical engineering student at UTS Sydney and volunteer with Engineers Without Borders was shot multiple times and died at the property.

“A young man has lost his life today and that’s obviously just tragic,“ Acting Superintendent Gretchin Atkins said.

She confirmed some family were at the home at the time of the shooting, and the offenders fled the scene before emergency services arrived.

Marco Tapia. Credit: Marco Tapia/LinkedIn

Police believe the shooting was a targeted attack, but detectives fear it was a case of mistaken identity.

Tapia was only known to authorities because of a traffic offence and had no links to organised crime.

An alleged member of the Coconut Cartel posted to Instagram shortly after the shooting, appearing to reference Tapia’s death.

“Popped the wrong person. Didn’t even get the right house,” the post read.

Atkins said authorities are aware of the commentary online.

“We’re aware of those online social media posts and everything is under consideration,” Atkins said.

A man in his 20s has been killed in a shooting in Glen Alpine, Sydney. Credit: 7NEWS

Family and friends have been at the house on Tuesday, and are assisting police while the manhunt for those responsible is ongoing.

Neighbours told 7NEWS there were two suspicious cars in the area on Monday.

NSW acting premier Prue Car said the shooting was “a tragic event”.

“This is extremely concerning and really upsetting for that local community for that to happen,” she said.

“We send all of our thoughts and condolences to the family of the man involved.

“It’s an open police investigation, and we want to let police do their work.”

A man in his 20s has been killed in a shooting in Glen Alpine, Sydney. Credit: 7NEWS

Opposition Leader Kellie Sloane said her thoughts were with Tapia’s family.

“It is just tragic. Gangland war is out of control on our streets in Sydney. Fifty shootings this year alone,” she said.

“It’s terrifying. This is Sydney, not Colombia.

“What is this government doing? It is out of control, and something needs to be addressed immediately.”

A police investigation is underway, and a report will be prepared for the coroner.

Anyone with information should contact Crime Stoppers.