He chased the caretaker and a teacher who barricaded themselves inside a classroom and phoned police.
After failing to gain entry to the classroom, the man ran off and came across 36-year-old mum-of-one Marteine Robin who was doing a routine early morning delivery of pies to the Christchurch school.
The knife-wielding man opened the passenger door of her truck and got inside.
She told him to "get the f*** out'' of her delivery truck, but he responded by forcing her at knifepoint to drive him across Christchurch, and then stabbing her in the shoulder.
"I thought he had punched me and struck a nerve in my shoulder and made my arm go dead, but then I felt blood running down my back and I realised he'd stabbed me,'' Ms Robin said.
"I feared the worst, I thought I was going to die.''
Ms Robin eventually managed to escape when the man was momentarily distracted at a traffic jam almost one hour, and 50km later. But the drama only escalated when the man left the truck near the busy intersection of Hoon Hay and Halswell roads and then almost fatally stabbed a Christchurch City Council worker who intervened.
The council worker, described as Mr Thompson by police today, woke up from an induced coma and is in a stable condition.
Detective Inspector Greg Williams said this afternoon he was "improving all the time'' and would soon be moved to a ward.
He has given police a "preliminary rundown'' of the incident which resulted in him receiving "multiple stab wounds to the upper body''.
Mr Williams said: "He went through what took place when this 27-year-old male got in the car with him - it was obviously very traumatic for him.''
Construction worker Jade Lynn, 22, saw the attacker rampaging between vehicles and approached him with a crowbar, striking him in the neck, and herding him away from other members of the public.
Eyewitnesses described Mr Lynn as a "hero'' who prevented further injuries.
The armed man was only stopped when pepper sprayed, tasered and then shot twice by a female police officer.
Armed with a Glock pistol, she fired two shots, one hitting the local man's shoulder and the other his wrist.
The Independent Police Conduct Authority has been notified and will investigate the officers' actions. She has been praised by her superiors.
Detective Inspector Williams said police had spoken with the other victims again today to "see if they are okay.''
"There's obviously been some major trauma there,'' he said.
Victim Support have been called in to speak to them and provide support for Mr Lynn.
Today police interviewed other eyewitnesses and have been trying to piece together the movements of the attacker, from the time he left his Sockburn home, where he lives with his family, at 4pm on Wednesday night, to when he was found at Redwood School.
There have been unconfirmed sightings of the man at Jelly Park in Christchurch.
Williams, speaking at Christchurch South police station this afternoon, refused to confirm whether the man was known to police.
He could not offer a motive, but added: "I would have no doubt that when this man is charged, that we'll be seeking a psych assessment report.''
Police today met with the man's Somali parents, who Williams said are "absolutely devastated'' at the incident.
