Two men have been seriously injured in an attack on the grounds of Wheatfield Prison in Dublin.
Gardaí said the men, aged in their 20s and 40s, were taken to Tallaght University Hospital after the attack shortly before 3pm today.
They said several men are believed to have been involved in the attack.
Shortly after Gardaí stopped a vehicle carrying a number of people on the Kennelsfort Road.
A number of people were arrested and taken to separate garda stations in Dublin.
The scene has since been cleared and the vehicle taken away for a forensic examination.
Gardaí are appealing to anyone who was travelling in either direction on the Cloverhill Road, between 2:30 pm and 3:15 pm to come forward.
They are particularly interested in talking to drivers who may have dashcam footage.
The Garda investigation is ongoing.