Just before 04:00 on Monday night, police rushed to Kungsgärdet, also called Studentstaden, where a boy is said to have been robbed by several people.
They allegedly beat him and stole cash and mobile phones.
A man in his 20s was arrested nearby, suspected of the robbery.
Early on Wednesday morning, at 04.48, a person is said to have threatened a boy and taken his mobile phone and other belongings.
In this case, no suspect is found.
At midnight on Thursday night, another boy was hit, this time in Gränby.
Several people are said to have threatened a 15-year-old boy and taken his moped.
When the police arrived at the scene, the robbers were gone.
"Keep your eyes peeled"
- We do not suspect any connection at the moment.
Unfortunately, we have a development where young people commit these crimes against other young people.
You have to make people aware of this, so that you have your eyes on it and it has a crime-preventing effect, says Jonas Eronen, the police's spokesperson.
He emphasizes that there is a long-term preventive work, between the police, social services and school.
- But we still have a long way to go, and long-term crime prevention is required throughout society.