Phua said two teen girls allegedly dragged his mum out of the car and viciously beat her up before driving off with her car and all her belongings. Voon was taken to Auckland City Hospital Emergency Department unconscious with concussion, broken teeth, a fractured nose and bruising around the face and body.
"They left her there to die. There was blood everywhere. All her clothes and the hospital sheets were all bloody."
Police said two teen girls are suspected of carrying out the attack and stealing the woman's grey 2010 Toyota Corolla.
Phua said his mum woke up crying around 6pm tonight and was having continuous panic attacks and vomiting before she was sedated.
WATCH: Family speak out on carjacking: 'She was an easy target'
The family haven't experienced much racism since moving from Malaysia in 1991 "but there's always a first", said Phua. He thinks Voon was picked on because she was 65, 45kgs and alone. Phua is speaking out because he doesn't want this to happen to anyone else.
"You don't take notice of [assaults] until they affect you. It's becoming more common now to Asian because they're easy targets.
"A key thing is [Asians] don't speak out if anything happens to them.
"She's lucky to be alive, but maybe the next person won't be so lucky."
Phua said the whole family are shocked and shaken that this has happened.
"This is our home. We trust and feel safe here. But we've got doubts now. It's good that other people should know. They need to be careful."
Voon is usually a fit, friendly woman who spends her time going to church, swimming and seeing her friends. Phua said she has been keeping herself busy after her husband died three years ago.
Voon's daughter, Carmen Phua, 43, said it was so unnecessary for the offenders to beat her mother up. They could have stolen the items without inflicting grievous harm.
"They could have taken what they wanted and run. They didn't need to beat her up.
"This is quite dramatic for an old lady, it's so unexpected. Her whole body is shivering.
"We need [these] people to be locked up. I think the law is a bit too relaxed. Teenagers only get community work."
Auckland City Police tonight released CCTV footage of the two women wanted in relation to the carjacking and assault. The video shows a red Honda pulling up blocking the victim's car from reversing. Two women get out of the car and pull the victim from her seat.
Police have chosen not to show the footage of the violent assault that happens next.
"The victim tries to run away but is followed by the women with the object in her hand. She is struck several times in the head with the object and is then kicked in the head as she falls to the ground. The women in the grey-hooded sweatshirt hops into the driver's seat of the victim's car and the assailant gets in the passenger seat.
"The victim is lying behind the car and the assailant gets out of the car and shoves her out of the way as the car reverses. The victim manages to get up and run for help as the two cars then speed out of the carpark."
Auckland City Police Detective Sergeant John De Heer wants to hear from anyone with information on the assault.
"We want to hear from anyone who knows who these two women are. This was very violent and the footage of the assault is quite alarming.
"It may be that these women have been scoping out other carparks prior to this and have appeared suspicious, they may well have been driving erratically after this incident too."
The victim's grey Toyota Corolla was found abandoned just after 5pm in Mangere. It has been towed away by Police to be forensically examined.
A police spokeswoman said police were looking for two teens, believed to be Maori or Pacific Islanders.
She said the teens may have arrived with a third person in a red 2002 Honda Fit that was reported stolen earlier today.
Anyone who sees the Corolla (registration FQP125) or who saw the persons described in the red Honda Fit (registration EZD733) prior to, or after today's incident is asked to call police immediately on 111.