A police spokesman said the trouble started when a woman, who was driving along Cranbourne Road about 1.30pm, tooted her horn at a man who cut in front of her.

He pulled alongside her car and forced her off the road.

"Another driver who saw the incident put his car between the woman's car and the offender's vehicle.

"The offending driver has then tried to force this second driver off the road."

The good Samaritan drove off but got out of his car at traffic lights when he realised the offending driver had followed him.

"This driver grabbed an iron bar and chased the man back to his car and broke the passenger window of his car.

"As the offender drove away, he swerved his vehicle at the man, but did not hit him."

A 29-year-old Frankston man has been charged on several counts and has been bailed to appear in the Frankston Magistrates Court on October 8.

Any witnesses to either of the incidents can call Crime Stoppers on 1800333000.