There has been a serious accident on the TT course, involving a number of motorbikes.
It happened at lunchtime near Alpine Corner.
The road has been closed between Douglas Road Corner, Kirk Michael and Ballaugh Bridge, although access is available to Kirk Michael.
Emergency services have been at the scene and it's understood traffic has been backing up due to the road closure.
The advice from police is to avoid the area, unless absolutely necessary.
There are currently no details on any injuries.