A teenage boy shoved a pensioner to the ground and started kicking him after his victim asked him not to bang on his car.
Police appealed for witnesses after the 72-year-old driver was treated in hospital for shock and suffered cuts and bruises.
The OAP, who has a heart condition, was brutally assaulted after he heard a bang on his car as he slowed down to let a girl cross the road ahead of him.
He was attacked last Friday afternoon, after he got out of his car and asked a boy if he had hit it.
The attack happened near two secondary schools and a school for children with behavioural issues in Eastbourne, East Sussex.
A spokesman for Sussex Police said: “It happened at 3.15pm on Friday outside a school as the man slowed his car to allow a girl to cross the road ahead of him.
“As he did so, he heard a bang on his vehicle, stopped and got out to ask a boy who was nearby if he had been responsible for the noise.
“The boy responded by knocking the man to the ground and then kicking him, causing him to sustain cuts and bruises. The victim also suffered shock.”
The attacker is is described as a fair-haired white boy in his teens, 5’7″ to 5’9″ tall.
He was wearing a dark jacket and light grey tracksuit bottoms.
By Berny Torre