We have reason to believe that he was injured before he crashed into the tree, but we don't know that for sure, says the police's press spokesperson Mats Eriksson.
Witnesses are also said to have seen several people leaving the scene after the accident, and heard the sound of shots.
We don't know if it's about people who left the vehicle or the area around the vehicle, says Mats Eriksson.
The national bomb squad is also on site, working to investigate the car.
There are damages to the vehicle that have made us want the national bomb squad to take a look at them to see how they occurred.
A technical examination of the car will also be carried out.
The police initially classified the incident as attempted murder, but the classification was later changed to murder. No one has been arrested at present.
We have checked a lot of people and none of them are detained. Now we will talk to witnesses and create a picture of what has happened, says Mats Eriksson.
The alarm came in to the police at around 20 o'clock on Tuesday.