A man in his 60s has been stabbed in the neck at a campsite in Trollhättan, reports Expressen.
A 25-year-old man has been arrested on suspicion of attempted murder. Another man has been taken in for questioning.
There has been some kind of fight and we don't know exactly how many were involved, says Morten Gunneng, officer in charge, to the newspaper.
The injured man was conscious when the police arrived.
Corrected: An earlier version contained an incorrect statement about a detention.