In October, the teenager drove a car that was illegally reformatted to an a-tractor in Vindeln.
He lost control of the vehicle and skidded into another A-tractor.
Between the vehicles was a guy who was squeezed and had to seek hospital care.
When the police arrive at the scene, the guy had already been taken away by ambulance.
The injured person had to undergo surgery and the National Board of Forensic Medicine writes that the injuries are considered life-threatening, among other things due to the great risk of serious infection.
In a forensic certificate from a specialist doctor, it is too early to judge which ones the guy will get.
However, there is a risk of stiffness and persistent pain from the injuries.
Found weapons in the hand compartment
In the police's technical investigation, an air pistol and a magazine were found in the hand compartment of the teenager's A-tractor.
The teenager tells in interrogation that he would take it to a relative to shoot at paper boards with supervision.
The teenager is charged at Umeå District Court for causing bodily injury, illegal driving, negligence in traffic and minor gun crime.
He denies all charges.