Poland School Knife Attacks: Woman Arrested in Third Stabbing

Warsaw, May 9, 2026 — Police in Warsaw arrested a 21-year-old woman on Saturday after she allegedly used a sharp object to injure three people at a school in the Polish capital. The assault marked the third knife attack at a Polish school in less than a week and came a day after thousands of police officers were deployed to schools nationwide.

A spokesperson for the Warsaw police told the PAP and AP news agencies that the suspect attacked a 17-year-old girl inside an educational facility using a “dangerous object.” The teenager, whose injuries were not life-threatening, was taken to a hospital. Polish state media reported that two other women, aged 17 and 24, were also hurt while they were at the school to submit enrolment documents.

Initial findings suggest the suspect is a student at the school and that she did not know any of the three victims, police said. The Warsaw department did not confirm whether the case was linked to the two earlier attacks that have raised concerns about school safety across Poland.

The latest incident followed a series of violent episodes. On Wednesday, a 19-year-old student attacked nine people at a vocational school in the central province of Mazovia. A day later, a 15-year-old entered a primary school in Leszczydół-Nowiny, north of Warsaw, and killed a 37-year-old caretaker. That attack was the deadliest in the current series.

Police across Poland had been on high alert after those incidents. In a coordinated operation, officers visited schools nationwide and detained 76 people, according to Polish police. Prime Minister Donald Tusk said before the deployment: “When it comes to the safety of Polish children and peace in our schools, there is no room for compromise.”

Interior Minister Marcin Kierwiński also reported that a 17-year-old was detained in Sierpc, north-west of Warsaw, after allegedly saying on school grounds that he intended to harm someone. No charges have been announced in that case, and local authorities have not said what happened to the teenager.

Investigators have not ruled out a connection to online challenges. Local media, citing a police spokesperson, said authorities have information suggesting the recent attacks could be linked to an internet challenge. The details of that challenge remain unclear, and police have not identified any specific platform or post.

Security analysts who study school violence in Central Europe said the rapid sequence of attacks fits what criminologists call a contagion effect. According to this view, heavy media coverage can encourage copycat behaviour, especially among adolescents who feel isolated or seek attention. The fact that Saturday’s attack happened during a high-profile police operation made that dynamic especially striking.

While the motive in Saturday’s attack is still unknown, the case has reignited debate about how far schools should go to prevent similar incidents. Some local governments in Mazovia have announced security reviews, and principals are being asked to pay closer attention to changes in student behaviour. Teachers have also been reminded to report suspicious statements immediately to police.

Under Polish law, the 21-year-old suspect can be held for up to 48 hours before prosecutors decide whether to charge her. Police have not released her name, and it is unclear whether she has a criminal record or a history of mental health treatment. A forensic examination will determine the exact nature of the “dangerous object” she is accused of using.

The three injured women are expected to recover. The 17-year-old remains in hospital under observation. The caretaker killed on Thursday has not been publicly named by authorities.

Public concern has also grown over the possibility that other students were planning similar attacks. Polish police said the nationwide operation was intended to deter violence, but the arrest on Saturday showed that a visible police presence does not always stop a determined attacker.

Education officials in Warsaw have not announced changes to the school calendar. However, extra patrols and emergency briefings are expected to continue through the weekend and into the opening days of next week. The government has not introduced metal detectors at school entrances, but some individual municipalities have said they will review the idea.

Analysts argue that preventing another attack will require more than security infrastructure. Schools in Poland have limited access to school psychologists, and waiting lists for adolescent mental health services can be long. This week’s events have put pressure on the government to respond with measures that address both security and mental health.

Police have asked parents and students to report any concerning online content. Warsaw police encouraged schools to contact the nearest station if they received threats or saw posts that suggested violence. The authorities also warned against spreading unverified rumours on social media.

As of this writing, no formal charges have been filed against the 21-year-old woman. The investigation is still in its early stages, and police have promised to release more information once the forensic report is complete. The question now is whether the next few days will bring more arrests — or a return to calm.