At least seven people were hurt when the teenager drove a car into them, including a 17-year-old who is severely injured. He was taken to hospital by helicopter.
The group were standing at a bus stop by their school in Diepholz, Lower Saxony, when the 18-year-old drove into them at 8am.
Police said they had several witnesses who led them to the driver. He was arrested shortly afterwards.
The incident took place in front of dozens of students at the school. “Many of the young people are suffering from shock,” police said in a statement.
Emergency services have been at the school all day.
The investigation is continuing.
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