A 15-year-old with a helmet camera kills a caretaker at a Polish primary school

A 15-year-old former pupil killed a caretaker and injured two staff at a primary school in Leszczydol-Nowiny on Thursday morning, and he was wearing a helmet with a camera fitted to it. Prime Minister Donald Tusk said the boy appeared to have intended to film the attack. It was Poland's second school stabbing in two days. Police say they stopped a third plan the same day.

The attack began at about 9am local time, 7am GMT, at the John Paul II primary school north-east of Warsaw, in Wyszkow county. The boy had studied there and no longer did. Interior ministry spokesperson Karolina Galecka said he was carrying three knives. Polish media, citing police, reported that the caretaker tried to stop him at the door. She was 37. A teacher and the headteacher overpowered him and were both injured. Their lives are not in danger, Galecka said. The boy's motive has not been established.

Tusk called an emergency meeting and said the country was in an extraordinary situation. He said this was the first time authorities were dealing with a killer who wore a helmet-mounted camera in order to film a knife attack. He said he feared a grim copycat phenomenon. Local media, citing a police spokesperson, reported that investigators have information suggesting the incidents of the past two days may be linked to an internet challenge. That link is a police lead, not a published finding.

The day before, in Ostroleka, also in the north-east, a 19-year-old wounded 10 people, including himself, at another school. BBC's count of the injured in that attack, excluding the attacker, was nine. Either way it was a mass injury at a school, and it was still being processed when Thursday's attack began. In Sierpc, north-west of Warsaw, a 17-year-old was detained after he said on school grounds that he planned to do something dangerous and intended to harm someone. Teachers called the police. Officers found two knives. Interior minister Marcin Kierwinski gave that account.

Three cases in two days, two of them completed attacks and one interrupted, are what pushed Tusk to use the word copycat. The camera is the detail that separates Thursday from an ordinary school fight. A helmet-mounted camera is equipment. It implies a plan to record, and a plan to record implies an audience. Investigators have not said the footage was streamed, or that a platform has been identified. They have said the camera was there, and the prime minister has said the intention was to film.

The caretaker's role in the account matters. She was not a random adult in a corridor. Reports say she tried to stop a former pupil from entering. Primary schools in small Polish towns do not have airport-style doors. The adult at the entrance is often a caretaker. She is the person a boy with three knives meets first. That is the sequence Galecka's briefing and the local reporting support.

Poland does not have a pattern of school shootings on the American scale. Knives are the weapon in these cases, and the ages run from 15 to 19. The policy question Tusk's meeting will have to answer is narrow: what a school does on Friday morning about a former pupil at the door, and what police do with a tip that a teenager has said, on school grounds, that he means to hurt someone. Sierpc is the case where that tip worked. Leszczydol-Nowiny is the case where the caretaker met him first.