One person has died following a road traffic collision on the Glenshane Pass in county Londonderry.
Members of the public were urged not to attend the A&E department of Altnagelvin hospital for a number of hours.
It's believed two vans and a car were involved in the crash with at least five casualties.
Paramedics and medical staff worked with those injured at the scene.
One woman was airlifted to the Royal Victoria Hospital in Belfast.
The road has now been re-opened but drivers are asked to maintain caution with poor conditions expected overnight.
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