A man in his 50s was killed in the collision.
A man killed in a Westmeath crash may have been left undiscovered for a number of days.
Gardaí were alerted to the incident yesterday evening, after Marcin Nowosielski's car collided with a ditch on the Castlepollard to Coole road.
He was the sole occupant of the car.
Officers are continuing to investigate the matter, and are asking anyone with information to contact Mullingar Garda Station.
Firefighter and Fianna Fáil Councillor, Alfie Devine, says the crash may have occurred on Sunday:
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