Driver suffers serious injuries during Isanti County Fair demolition derby 

CAMBRIDGE, Minn. (FOX 9) - A driver at the Isanti County Fair was airlifted to the hospital after a crash during a Grandstand event Thursday. 

Man injured during demolition derby in Isanti County

What happened:

A man was airlifted to the hospital after a collision during a Grandstand event at the Isanti County Fair, fair officials say. Officials said that the driver sustained life-threatening injuries and was air-lifted to North Memorial Hospital.

The Isanti County Fair's website shows that the fair's Grandstand event on July 17 was called "Night of Destruction", a demolition derby event. The competition included four, six and eight-cylinder vehicle races. A backwards race and a trailer race were also listed in the event description. 

The fair canceled its "Night of Chaos" autocross racing event that was planned for Saturday. 

The Isanti County Sheriff's office says the crash is not being investigated as a criminal matter, and they don't have any updates on the status of the driver. 

What we don't know:

Officials with the fair did not state what led up to, or what caused, the crash.