A 15-year-old former student killed one person and injured two others at a Polish primary school on Thursday, police said, just a day after a 19-year-old wounded 10 people, including himself, in an attack at another school.
Authorities said a 37-year-old woman who worked as a caretaker had died in the attack, which took place at around 0700 GMT in Leszczydol-Nowiny, in Wyszkow County northeast of Warsaw.
"She was the first person attacked with a sharp object," police spokesperson Katarzyna Kucharska told private broadcaster TVN24. "The principal heard the screams and attempted to restrain the attacker, assisted by a teacher - both were injured."
Interior Ministry spokesperson Karolina Galecka said the lives of the two injured people were not in danger.
"The attacker was a former pupil of this primary school and is currently a student at a vocational school," she said. "At this moment, we do not know the motives. He was carrying three knives and attacked the caretaker."
A government spokesperson said Prime Minister Donald Tusk had called an emergency meeting.
POLICE PREVENT A SEPARATE ATTACK
Interior minister Marcin Kierwinski said that in a separate incident on Wednesday in Sierpc in north-central Poland police detained a 17-year-old who had spoken about plans to do "something dangerous" on school grounds.
"Teachers notified the police, who intervened and found two knives in his possession," Kierwinski told a press conference. "Data recovered from electronic devices revealed online searches regarding how to orchestrate such a violent event."
Ten people were injured in a knife attack at a school in Ostroleka in northeastern Poland on Wednesday, with police detaining the 19-year-old suspect, who was among those hurt, shortly after the incident.

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