A woman in her 50s has died and three others were injured in a crash on the N15 in Castlegal, County Sligo.
Gardai say the single vehicle collision happened at around 3.30am on Monday.
A man in his 50s, was brought to Sligo University Hospital in a critical condition.
Two others, the driver, a man in his 20s, and a teenage boy are also being treated there for non-life-threatening injuries.
Gardai say the woman was pronounced dead at the scene, her body was brought to Sligo University Hospital and a post-mortem examination will take place.
The Coroner has been notified
The road was closed for forensic investigations and has now reopened.
Gardai are appealing to anyone who may have witnessed the collision to come forward.
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