TRANSCRIPT:
For some motorists on the busy Princes Highway at Engadine, it seemed like an ordinary accident, with two cars colliding on Sunday morning.
This witness, Andrew, was among those quickly running to help - and to find this was a different situation.
"Just came flying up the road. And then he's turned up through, onto the wrong side of the road, went through through the traffic lights and as he's come through the lights there he's been t-boned. And then when he got t-boned he came out and yeah tried to slash up his partner. Police come up here and he's managed to slash up a couple of other people and another policeman and that too."
Superintendent Donald Faulds from the Sutherland Shire Police Command says that driver was quickly taken into custody.
"As the community members were assisting one of the females out of one vehicle the male got out of that vehicle. He was armed with what we believe to be a box cutter, and the female had obviously sustained a number of injuries from an altercation inside that vehicle... That male was engaged by the police. A short foot pursuit occurred. A taser deployment was initiated and that person was taken into custody."
Paul Tonge from New South Wales Ambulance says emergency services arrived to a distressing scene.
He says the woman, a bystander, and a police officer were all injured from an apparent stabbing.
"We treated and assessed six patients two of those were injured in the motor vehicle accident described before. Four of them had suffered stab wounds. One mild patient had sustained slash wounds to his arms and his neck and was transported to Liverpool hospital in critical condition, who is now said to be in serious but stable condition."
The man accused of the stabbing rampage and the woman passenger are also both now in serious conditions in hospital.
The Superintendent says they are known to each other.
"What I can say about the two occupants in the car where the female was stabbed and the driver self-inflicted a number of wounds to himself, they were in a domestic relationship. Again, there's no history that we're aware of. There's no apprehended violence orders between the two. But definitely domestic related."
Donald Faulds has credited the "amazing work" and bravery of those who intervened as the events unfolded.
One of those bystanders says everyone is still in shock over the turn of events.
"I was out there. I was out there. Me and my mate tried to restrain the guy. He pulled a knife. What am I going to do? I'm not taking a knife for anyone you know. The other guy who tried to help the lady, protect her - he got stabbed. So it's not right. It's not right."
