The alarm came in just after 8 pm on Sunday evening after several people alerted the police.
The man was detained just over an hour later after a large police operation.
According to the police, the man came to Stallarholmen in a stolen rowing boat.
The man, who according to the police suffers from mental illness, approached several people with an ax on him.
- The man must have contacted several people because he wanted drinking water.
It's obviously a scary situation for many that a man is walking around with an ax and is clearly threatening, says Johnny Gustavsson, press spokesperson for the police.
The police do not want to reveal the man's age, but he is in custody on suspicion of preparation for murder, breach of domestic peace and arbitrary proceedings.
No one should have been injured in the incident.