The case came in to the police shortly after 9 pm on Monday evening.
A man is said to have threatened a person in central Falun.
When the police patrol arrived at the scene, they were met by the man who had a knife in his hand.
- He released the knife quickly, so there was never a serious situation for the patrol, says Ola Olsson, officer on duty at the police's regional command center.
The man was arrested, suspected of making illegal threats against a person before the police arrived on the scene.
He was arrested later in the night towards Tuesday.
No person should have been injured.