Two incidents during the four lap Full Factory Winnerswear Senior Grand Prix brought racing to a halt on its final lap.
Three riders, Michael Moulai, Andrew Soar and Rob Hodson were contesting the lead with just a handful of seconds separating them when the course was red flagged.
The two incidents were at the 11th milestone and at Bishopscourt. The incident at the 11th involved three riders. All the riders involved have been taken to Nobles hospital but there are currently no details on their condition.
Riders were stopped at various parts of the course.
Shortly before 2pm, Clerk of the Course, Phil Taubmann, announced the race would not be restarted and the winners would be declared as of the end of lap two.
It means Andrew Soar was first with Michael Moulai in second and Rob Hodson third.
The MGP Riders Re-union Parade, which was due to have taken place after the race, has been cancelled due to the condition of the road at the 11th milestone.