Oil company representative Andrew Hobbs, who was driving with his wife and children on the way to work in Nelson, told Fairfax about coming across the burning wreckage and rushing to extinguish a fire that threatened to engulf the two cars involved in a high-speed head-on collision.
Police this morning released the names of the two people who died following the crash on the Waimate Highway on Boxing Day morning.
Horton James Hill, 80, of Christchurch and 31-year-old Matthew James Gilchrist of Oamaru died at the scene of a crash between Carrolls and Stangers Rds shortly after 8.30am.
Mr Hobbs said he was following a Holden Commodore travelling at a high speed - he believed between 140kmh and 150kmh - through Glenavy, north of Oamaru, and only moments later was first to come across the burning wreckage of the crash scene.
After putting his hazard lights on, he rushed towards the burning wreckage and quickly used his fire extinguisher to make the scene safe.
He believed the fire could have become more involved if he had not acted so quickly.
After that he checked both victims for vital signs and quickly realised that they were dead.
He said his first aid training and experience working for the Volunteer Fire Brigade in Kaiapoi kicked in after he came across the crash scene.
"I knew exactly what had happened, we have all seen it before ... it comes down to instinct ... you have just got to prioritise the situation and disassociate yourself."
His wife called the police.
He said he would be make a formal statement to police when he drove through Waimate on the way back to Dunedin on Sunday.
Police today said the investigation by the Serious Crash Unit and Waimate police into the circumstances surrounding the crash was ongoing.
Police offered their sympathies to the friends and family of the deceased at this tragic time.
Mid-South Canterbury area commander Insp Gaskin, of Timaru, said it was ''pretty apparent'' the northbound vehicle was travelling at well over the 100kmh speed limit when the crash happened shortly after 8am less than 1km north of Glenavy on State Highway 1.
''If you want to be hard-nosed and callous about it - if he was travelling at the speed limit, he would still be alive, and so would the other gentleman,'' Insp Gaskin said.
''Pretty clearly, from visiting the accident scene, it was obviously an incredibly high-impact crash. Two vehicles coming together at 100kmh in opposite directions produces an awful lot of kinetic energy - but one of the vehicles was travelling well in excess of that speed.
''One of the vehicles as a result of the impact has split and basically broken in half - half of that vehicle has ended up probably 40m to 50m up the road and across the fence and in a paddock,'' Insp Gaskin said.
The driver of the northbound vehicle that split in half was ejected from his vehicle.
The southbound vehicle was taken to Timaru so firefighters could extricate the driver's body.
