Second mass stabbing attack carried out, filmed in Poland in 'grim copycat phenomenon'

"We are facing an extraordinary situation... for the first time, we are dealing with a killer who wore a helmet-mounted camera, intending to film the knife attack," said Prime Minister Donald Tusk.

A 15-year-old former pupil killed one employee and injured two others at a Polish primary school on Thursday while wearing a helmet-mounted camera, the second school stabbing in two days, possibly in response to an internet challenge, authorities said.

A 37-year-old woman who worked as a caretaker had died in the latest attack, which took place at around 9 a.m. in Leszczydol-Nowiny, northeast of Warsaw, officials said.

On Wednesday, a 19-year-old wounded 10 people, including himself, at another school in Ostroleka, northeastern Poland, and police detained a 17-year-old in Sierpc in north-central Poland on suspicion of planning an attack.

"We fear a grim copycat phenomenon," Prime Minister Donald Tusk told an emergency meeting.

"We are facing an extraordinary situation... for the first time, we are dealing with a killer who wore a helmet-mounted camera, intending to film the knife attack." It was not clear whether the attack was actually filmed.

Teachers injured restraining attacker

He ordered police to visit schools daily in an effort to prevent further violence.

A police spokesperson said authorities had information that the incidents could be related to an internet challenge and that this was being investigated.

Tusk praised the heroism of two teachers at the school who were injured as they tried to stop the attacker.

Head teacher Krzysztof Ochmanski said he had heard a scream and ran into the corridor.

"He wounded me with the blade of a rather long knife - he had three knives on him - and hit me with the handle," he told the public broadcaster Polskie Radio RDC. "By then, I had managed to restrain him."

A Reuters reporter saw an air ambulance flying away from the school, where a small crowd had gathered. The father of one child, waiting outside the school, said pupils had not yet been allowed to leave, but were safe.

Serious offenders becoming younger across Europe

Footage on public news broadcaster TVP Info showed what appeared to be the attacker being handcuffed and put into a police van.

Inspector Katarzyna Nowak, director of communications for the national police, said serious offenders were becoming younger across Europe.

"Over the past few months in Poland, we have seen arrests of teenagers who were preparing to carry out attacks... So, this is indeed a problem we face, and one we must acknowledge," she told TVP Info.

Interior minister Marcin Kierwinski said that the 17-year-old detained in Sierpc had mentioned plans to do "something dangerous" on school grounds.

"Data recovered from electronic devices revealed online searches regarding how to orchestrate such a violent event," Kierwinski said. Police found two knives in his possession.