Detectives questioning five men in connection with the murder of a police officer in County Tyrone in April Five men have been arrested by detectives investigating the murder of Constable Ronan Kerr in Northern Ireland. The new police recruit was killed by an under-car booby-trap bomb that exploded outside his house in Omagh, County Tyrone, on 2 April. Kerr was killed by dissident republicans opposed to the peace process in Northern Ireland. He was one of a growing number of Catholic police officers joining the Police Service of Northern Ireland. It was one of the most serious incidents attributed to dissidents, who have also attacked police station and other security force targets. Police said searches linked to the arrests were under way on Tuesday in Coalisland, Toome, Bellaghy and Ballyronan, County Tyrone. Northern Ireland guardian.co.uk