An 18-year-old, identified as Liam Nebel, has been detained following a school attack in Fagersta, Sweden. The attack resulted in the death of a young girl and injuries to three boys. Nebel was formally arrested on Sunday and is facing charges of murder and attempted murder. The detention was ordered on probable cause, indicating authorities believe they have substantial evidence linking him to the crime. The incident has deeply impacted the community of Fagersta and prompted a large-scale police investigation. Further details regarding the motive behind the attack remain under investigation. This event raises concerns about school safety and mental health support for young people.