A patrol cruiser dashcam was rolling as a deputy with the Madison County Sheriff's Office jumped onto a moving semitrailer because the driver was having a medical issue.
Sgt. Todd Volk says he took the daring action and later discovered the driver was having a diabetic episode because of low blood sugar.
The video shows multiple deputies follow the semitrailer with lights and sirens on, though it continues down the highway.
As deputies followed, the vehicle slowed enough for Volk to make the rescue.
Paramedics arrived a short time after the stop. Volk says the driver was later OK.