Steve Mace Cronulla Sharks: Hero NRL footy club boss tells all after suffering knife wound while trying to protect his son during Sydney stabbing rampage

Cronulla Sharks chairman Steve Mace has given a traumatic account of the alleged stabbing rampage that occurred in Sydney's south on Sunday morning after he was hurt while protecting his son in chaotic scenes.

Emergency services rushed to Old Bush Road, near the Princes Highway at Engadine at around 9.15am on Sunday following reports of a multi-vehicle crash.

Several passengers inside the cars had allegedly suffered stab wounds and a police officer was also injured.

One person suffered a cardiac arrest, and a 40-year-old woman is among several passengers who have been rushed to St George Hospital.

Another patient suffered a stab wound to their abdomen while a third suffered a broken arm.

The alleged knifeman, 55, was treated by paramedics at the scene. He has since been taken into custody.

Mace revealed he suffered a cut to his hand when the alleged attacker turned his attention to his son Cooper amid the chaos.

The Sharks boss was driving his son to a junior football game when the accident occurred in front of them and he found himself embroiled in the horrible scenes as he got out to help.

'I could hear him [the alleged attacker] screaming but I could hear her [the passenger in a car] screaming more,' Mace told the Sydney Morning Herald.

'I ran around to the other side [of the car] ... I said, 'Stop, stop, leave her!' He said, 'No, f**k her. She changed my radio station.'

'Another bloke came to try to grab her out by the legs, but then the bloke [the alleged attacker] slit him right down his chest.

'He [the alleged attacker] went to go for Cooper and then I had to bolt around. Thankfully he kept raging and came back towards my side.

'He said, 'We're dying together, we're dying together' ... Eventually the cops were able to shoot him with the Taser.

'He ripped it out and ran up the road.

'I only got a cut to my hand but the other bloke [who helped the woman] copped a decent cut to his chest.'

A separate witness told Daily Mail Australia the 55-year-old alleged knifeman was pulling into Princes Highway in a white sedan when he was T-boned by a blue car.

He said a bystander rushed to the white car to help out and discovered the female passenger, 40, had been stabbed.

The driver of the white vehicle then allegedly stabbed the good Samaritan.

'He [the alleged knifeman] was ranting and then the police went to arrest him and were shouting 'get on the road' and he was trying to self-harm and he was cutting his own wrist and his throat' the witness said.

'Then they chased him up the front to my place and they were trying to revive him.

'He looked pretty bad. He was losing a lot of blood.'

Witnesses have reported seeing the white car travelling at speed through the area in the lead up to the crash.

The alleged knifeman, 55, was treated by paramedics at the scene. He has since been taken into custody.

Another witness told Daily Mail Australia he initially believed the stabbing and car crash were two different incidents because they happened at two locations about 200 metres apart.

He said he saw a blue and white car involved in a smash on the Princes Highway before another man was arrested near a black Hyundai further up the road.

'The crash happened down at the lights and there was a man ranting and raving there for about 20 minutes,' he said.