A ptor search effort was underway on Tuesday in Rissne in western Stockholm.
A man is said to have acted strangely and then climbed down a train track and into a tunnel.
The police later found the man, who was armed with a knife.
Shortly after 12:30 on Tuesday, an alarm was received by the police about a man behaving strangely.
– The public called and said they observed a man with very little clothing on. When we got to the scene, we made the same observation. Then the man ran down a train track in a tunnel in Rissne, said Ola Österling, press spokesperson at the police in Stockholm, shortly after the incident.
The police began a search in the tunnels, and after a while took into custody a man who was carrying a knife. A criminal investigation has now been launched.
In connection with the search for the man, all tracks were de-energized and a traffic stop was carried out between Rinkeby and Hallonbergen.
“The rail-bound traffic will shortly return to the tracks,” the police write in a press release at 12:45 on Tuesday afternoon.