Man with knife ‘punches off-duty cop in road rage episode’

A MAN hiding a knife has allegedly punched two people - one of them an off-duty policewoman - during a road rage incident in Adelaide's inner west.

Police were called to Henley Beach Rd, Brooklyn Park, after reports a Mazda sedan had stopped in front of a Mitsubishi 4WD to block its path about 11am.

The alleged offender got out of the Mazda and was about to confront the Mitsubishi driver when another man and woman approached him.

He punched both before members of the public stepped in and restrained him.

The woman - an off-duty police officer - and man have minor injuries.

A 31-year-old Morphettville man was arrested and will face assault and weapons charges. Police found him in possession of a knife during a search.