A 17-year-old is said to have injured a classmate at a Dortmund vocational college on Wednesday with a knife in the head. The youth was arrested and the 19-year-old victim was treated as an outpatient in the hospital, said a police spokesman. The police had moved out to a large-scale operation at the school.

The situation was unclear, said the police spokesman. In the meantime, based on numerous witness interviews, it is assumed that there was a dispute between several students. In particular, the 17-year-old and the 19-year-old clashed.

The 17-year-old was arrested shortly after the crime, but the police initially reported a second perpetrator who was on the run. This has now turned out to be a student who intervened to settle the dispute, said the police spokesman.

The 17-year-old suspect is accused of causing dangerous bodily harm. The suspected murder weapon was seized.