A father and son whose car burst into flames after veering off a motorway were saved by a passing fire extinguisher technician.
The men had to be cut free from the car after it burst into flames
They suffered serious head injuries when their car hit a road sign at junction 10 of the M23 in West Sussex.
The car caught fire but the flames were put out by the motorist on Tuesday.
West Sussex Fire and Rescue station officer Gary Towson said: "They might not have survived at all if it wasn't for the actions of the motorist."
A 46-year-old man is in a comfortable condition at the East Surrey Hospital, Redhill, while his 18-year-old son is critical but stable.
The man who saved their lives was Jon Paxton, who services fire extinguishers for a living and had several in his vehicle as he travelled southbound on the M23.
Mr Paxton said he just did what anyone else would do
He said he saw the car spin around, hit the sign and then burst into flames.
"There was a big plume of black smoke, so I slammed the brakes on because I knew that there were going to be people trapped," added Mr Paxton.
He crossed the busy carriageways and had to use three extinguishers to help the trapped pair.
Rod Cairncross, from West Sussex Fire and Rescue, said they would have been seriously burned if Mr Paxton had not intervened.