Road closed between Longford and Newtiownforbes
Update: A 23-year-old woman has been airlifted to Beaumont Hospital in Dublin following the serious collision in Co Longford.
The incident occurred on the N4 at Lamagh shortly after 3pm.
A garda spokesman said a woman in her 50s was arrested at the scene of the crash.
The road has been closed on the Longford town side of Newtownforbes.
Diversions are in place and a forensic collision investigator is en route to the scene.
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