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Irish police have raided a house in County Monaghan that may be connected to the murder of the Police Officer Ronan Kerr on April 2. Kerr died when a device planted in his car exploded as he prepared to drive to work in Omagh, County Tyrone.
Police are now forensically examining the house in Scottstown, Monaghan, close to the border.
On Tuesday two men were released by detectives in Northern Ireland investigating his death. One 33-year-old man remains in custody.
A spokesperson for the PSNI told the Press Association "As part of the ongoing PSNI investigation into the murder of constable Ronan Kerr and a subsequent arms find in Coalisland, a house was searched in Co Monaghan.
"The search was conducted by members of An Garda Siochana (Irish police), who continue to liaise with detectives investigating both constable Kerr's murder and the Coalisland arms find."
Weapons and explosives were discovered by police in Coalisland however none were seized in Monaghan. There were no arrests during the raid.
Although no one group has claimed responsibility for Kerr's murder it is believed that it was the work of a group of dissident republicans opposed to the peace process. It is believed he was targeted because he is Catholic and had recently graduated official as a police officer in the new-look police service which replaced the Royal Ulster Constabulary.