Dramatic footage has captured the moment an off-duty police officer wrestled a motorist to the ground, after he lunged at another driver he apparently thought was driving too slowly.Video of the extraordinary row shows an elderly man reaching in through the driver's window and tangling with him on the A27 Sompting bypass in Worthing, Sussex.He appears to try and grab at the driver as he is sat behind the wheel in a heated row until the off duty police officer intervened.