Two schoolgirls aged 13 and 14 were attacked by a man on Monday morning on their way to a school bus stop in Oberkirchberg (Alb-Donau-Kreis) in Baden-Württemberg and apparently seriously injured with a knife.
Both girls had to be treated in a clinic after the attack.
A special task force (SEK) was involved in the operation.
The police officers managed to track down the alleged perpetrator and put the man in a refugee shelter.
"Three men from this building voluntarily followed the requests of the SEK officers to come to the police station," said a spokesman for the Ulm police headquarters.
The connection between the three men and the attacks on the girls is currently being determined.
However, the police officer assumes that one of the men could be the alleged perpetrator.
The police did not want to comment on the murder weapon or the identity of the perpetrator.
According to a report by the "Südwest Presse", the house in which the three men were arrested is a communal refugee shelter.
It was unclear on Monday afternoon whether the alleged perpetrator lived there or whether he only spontaneously sought refuge there after the crime.
A family of seven and four men are said to be housed in the house.