Gardaí are investigating a fight between a number of men on the M50 in Dublin.
The incident happened around 6.20pm yesterday evening, when two cars stopped on the motorway between the Redcow and Ballymount junctions.
A number of people are then said to have become 'involved in an altercation'.
One man has been taken to Tallaght Hospital, and his injuries are not believed to be life threatening.
Another man was also injured, but refused medical attention before leaving the scene.
The incident caused serious disruption to traffic.
Gardaí are appealing for witnesses, or drivers who may have dash-cam footage of the incident.
They can contact Tallaght Garda station on 01-666-6000 or the Garda Confidential Line on 1800-666-111.