He suspected an arcing battery may have caused the fire.
"I noticed a bit of a flash when I looked back to check the load. I pulled over and had a look and couldn't see anything."
He continued to head towards his Kerikeri depot but 600m along the road he was forced to stop.
"It just blew up and was engulfed. It is one of the potential dangers of the job," he said.
Following safety procedures learned during rigorous training sessions for such situations, Mr Zaloumis was able to quickly and safely get the flaming vehicle on to the road.
"We have procedures for these situations and our equipment is all geared up for quick release. It took me about a minute and a half and I had all the vehicles off."
Having previously been a volunteer firefighter with Newlands Brigade in Wellington for four years, Mr Zaloumis said he was cautious not to dump the car into scrub that could also ignite.
Once the burnt out car was doused and the vehicle had cooled off it was reloaded and taken to the yard in Kerikeri. It was a late night for Mr Zaloumis who made it home at 3.30am.
He reckons damaged cars bursting into flame while in transit was rare but this was the second time in four months he had been faced with a blazing vehicle on the back of his tow truck.
The previous incident involved a vehicle that had been burnt out on Omaunu Rd, near Kaeo. It had been wet down by Kaeo firefighters but while on the trip back to Kerikeri the vehicle reignited.
Conveniently he drove to the Kaeo fire station, phoned the chief, and had the fire put out while the vehicle remained on the truck deck.
"Car fires are hard to put out as the steel frames stay hot for a long time," he said.
Kaeo fire brigade fire officer Lindsay Murray said the two cars involved in Thursday night's crash collided head-on.
"The two cars were headlight to headlight and really smashed up. One of the drivers was trapped."
The brigade along with volunteers from Kerikeri set up lighting to allow a police serious crash investigator to survey the scene.
They also put in place cordons so the rescue helicopter could land on the road to collect the injured drivers. They had returned to the Kaeo station but had not had time to change out of their gear before the siren sounded and they were called to the car on fire on the back of the tow truck.
"The Kaeo firemen are a bit ugly today, we haven't had out beauty sleep," Mr Murray said.
Police were continuing to investigate the cause of the crash.
