The sole occupant of the car, a man in his fifties, was pronounced deceased a short time later.
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The road at Killaderry was closed for technical examination by Garda Forensic Collision Investigators, and has since reopened.
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Gardaí are appealing for any witnesses to this collision to come forward.
Any road users who may have camera footage (including dash-cam) and were in the area at the time are asked to make this footage available to Gardaí.
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Anyone with any information is asked to contact Tullamore Garda Station on (057) 9327600, the Garda Confidential Line on 1800 666 111 or any Garda station.
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