Policing patrol on the Irish border with a PSNI officer
Northern Ireland's chief constable has rejected claims that threats to security at the Irish border after Brexit are being exaggerated.
George Hamilton told the BBC it would be foolhardy for police not to prepare for a potential increase in tensions.
The BBC's Ireland Correspondent Chris Page has been on patrol with an officer based near the border in County Armagh to get a sense of the challenges of policing the border.