The accident happened at 04.30.
Three of those involved were able to get out of the car themselves. Two had to be extricated by emergency personnel.
– The driver and three of the passengers have been taken to hospital, says police spokesperson Mats Öhman.
Three people were not judged to be seriously injured at the first assessment, one is seriously injured.
All involved are in their 20s.
The road was closed in connection with the rescue work.
The police have launched an investigation into causing bodily harm and negligence in traffic. The car has been impounded for a technical examination.