The Department of Infrastructure says work to resurface the Mountain Road has overrun.
It closed the route from the Creg ny Baa to the Bungalow at 6pm last night to resurface 200 yards of road.
It's after contractors spilled bitumen on it.
On Facebook, the department says it had hoped to reopen the route by 6pm this evening, but the closure will now be extended until 8am on Saturday.
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