Confronting footage has emerged of the moment police arrested a teenager across the road from where he allegedly bashed a woman to death outside her home in Sydney's south-west.

Sprawled in the gutter and held to the ground, a handcuffed Imaueli Jone Degei has no way of escaping police following a short pursuit on the streets of Carramar, despite the rugby player's 130 kilogram frame.

The Airds man 18, is accused of murdering Kristina Kalnic, who died from critical injuries in the driveway of her Sandal Crescent unit complex on Saturday.

He was charged with one count of murder on Sunday.

The dramatic moment Imaueli Jone Degei is arrested by police as the woman he's accused of bashing is losing her fight for life

Imaueli Jone Degei, 18, (pictured) was charged with count of murder and refused bail when he appeared in court on Sunday

Chilling footage has also emerged of police and paramedics frantically trying to save the life of a motionless Ms Kalnic but to no avail.

The court heard Degei needed medication for mental health issues when he appeared in Parramatta Bail Court on Sunday.

He didn't apply for bail, which was formally refused by Magistrate John Crawford until his next court appearance October 22 at Fairfield Local Court, The Daily Telegraph reported.

Kristina Kalnic (pictured) died in the driveway of her Carramar complex on Saturday

It's since been revealed Ms Kalnic had lived at the unit complex with her husband for 20 years and had been the building manager at the unit complex for almost a year,

She was well-liked in the area and led a quiet life, according to shocked neighbours, who laid floral tributes in the well-tendered garden Ms Kalnic took pride in.

Police and paramedics frantically tried to save the life of a motionless Ms Kalnic in the driveway of her unit complex but to no avail

An Airds man, 18 has been charged with murder in relation the death of Kristina Kalnic outside her Carramar unit complex (pictured) on Saturday

'Why happened with her? Why she. People need her,' a distraught Bhakti Panchal told 9 News.

Neighbour Ula Naitokatoka, 21, was at home when she heard Ms Kalnic's screams added: 'She's a nice lady.'

Another man told 7 News: 'I've lived here for five years and nothing like this has happened before ever, so it's a bit of a shock.'

Paramedics were unable to revive Kristina Kalnic, 64, who died at the scene

Marina Manic studied psychology with Ms Kalnic at Western Sydney University five years ago.

'She was so wise and I learned so much from her,' Ms Maric told the Sydney Morning Herald.

'She was an incredibly intelligent woman and she never stopped learning, ever. That's what she wanted to do, her whole life was about that.'

A NSW Police spokeswoman told Daily Mail Australia that the alleged incident wasn't domestic related and that no weapon was used in the alleged attack.

It's unknown whether Ms Kalnic knew her alleged attacker as some residents told The Daily Telegraph they had seen Degai in the area previously.

Strike Force Bilba has been formed to investigate the death and inquiries are continuing.

Anyone with information is urged to call Crime Stoppers on 1800 333 000.