A womans car was punched and kicked in an “alarming” attack in Potters Bar.
Police appealed for information to track the man responsible.
Officers say a driver in a blue Nissan Micra was waiting in stationary traffic in Mutton Lane waiting to turn left into Tesco when the attack happened.
As the lights turned green, a man, thought to be in his late 50s or early 60s, moved in front of the car and hit it with his fists.
He then kicked the vehicle, before moving off in the direction of Willow Lane.
After the victim parked in Tesco, the man appeared again, and continued to attack the car.
He was then seen talking to a woman in a white short sleeved top and denim skirt before leaving the area.
The drama unfolded shortly after midday on Monday, June 3.
PC Gareth Clifford, investigating, said: “This was an alarming incident which would have been witnessed by several people as it was a busy time of day.
“I would urge anyone who may have seen the incident at the traffic lights or the incident in the car park to get in touch with us.
“I am particularly keen to speak with the lady who was wearing the denim skirt and white short sleeved top to get in touch with us as you may have vital information which could assist our investigation.”
The attacker is described as white, well built and around 5ft 9ins tall.
He had a tan and freckles and grey hair, which was combed to the side and had blue or green eyes.
He was wearing a grey or beige T-shirt and loose fitting blue denim jeans.
Anyone with information is urged to contact police by calling 101, quoting crime reference J1/13/490.
Alternatively, call Crimestoppers in confidence on 0800 555 111.