Witnesses told the Mercury the driver of a car and the rider of a motorcycle got into an argument near a strip of shops along Farmborough Road about 10.30am on Tuesday.

One witness said the two vehicles stopped, and as the rider advanced towards the car "screaming and yelling", the car's driver panicked and reversed into a pole.

"The guy in the car was scared, he tried to get away but lost control and hit the pole. I thought he was trying to hit the biker ... it was very entertaining," said the bemused shopkeeper, who watched the entire incident unfold.

The car then appeared to drive towards the motorcycle rider, who was said to have then smashed the car's window and body with his helmet.

"He was really attacking the car," the witness said, adding the rider was talking about being filmed by the driver while riding.

"It was very scary."

The car driver was said to be in his mid-20s, while the motorcycle rider was believed to be in his late 40s.

The car damaged the light pole, which fell and brought down power lines across the road. Traffic was blocked in the area for around 30 minutes, according to the witness.

The motorcycle soon left the scene, but the car - seen to be bearing damage to several panels - was later packed onto a flat-bed truck.

Lake Illawarra police said they had received no information about the altercation.