Occupants treated for injuries by ambulance crews
The route has been closed in its entirety since before 2pm this afternoon following the incident near to Kate's Cottage.
Fire crews from Douglas and Ramsey were called to the scene to stabilise the vehicles and free the casualties using cutting equipment, who were then seen to by paramedics.
With heavy fog on the mountain today, drivers are being urged to take care and drive to the conditions.
It's understood that the Mountain Road remains closed.
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