Investigators are examining a homemade explosive device found in a backpack thrown into a classroom during an attack at a vocational school in Ostrołęka, Poland, the national prosecutor said.
A teacher and students threw the backpack out of a window, which may have prevented the device from detonating, Prosecutor General Dariusz Korneluk told TVN24, according to Gazeta.pl. Experts are examining the item.
Investigators say a 19-year-old student injured seven people at the school, including two teachers and five pupils. He then left the building and attacked a man who was walking with his adult son, who has a disability. Police detained the suspect near the city beach, about 400 to 500 metres from the school. He was injured and taken to hospital.
Students told Polish media that the suspect had written about a plan to draw attention on his birthday. Those details were reported by local outlets and attributed to witnesses. The investigation is ongoing.
Police interviewed students and assisted with their evacuation from classrooms. Authorities have not officially confirmed a motive.