Poland puts 10,000 schools on alert after 'Bloody Friday' threats online

Polish police arrested about 10 people, most of them teenagers, across the country on Friday after a wave of online posts warning of a so-called "Bloody Friday" attack on schools, and placed roughly 10,000 schools on alert, authorities said.

In Szczytno, north-eastern Poland, officers detained a 16-year-old who had recorded and shared a video threatening named pupils and teachers at a local school; he told police he had made it "as a joke". In Warsaw, a 13-year-old was detained after posting a photo of a knife in a school class chat group and threatening classmates, and a 14-year-old was arrested at his own school after officers found a knife and fireworks on him. Two 15-year-olds from Pruszków district were also arrested after posting a video making threats online.

Poland's digital affairs minister, Krzysztof Gawkowski, told broadcaster TVN24 that false information and emotional reactions were circulating online, driven by public anxiety, but that police had so far found no evidence of an organised, nationwide "challenge" behind the threats. He said isolated or copycat acts could not be ruled out.

The alert followed two real knife attacks at Polish schools earlier in the week. On Thursday, a 15-year-old former pupil killed a 37-year-old school employee and injured the headteacher and a teacher who tried to stop him, at a primary school in Leszczydol-Nowiny, near Warsaw. A day earlier, in Ostroleka, a 19-year-old injured nine people, including himself, in a separate knife attack at a vocational school.

Police said they had also detained a 17-year-old in Sierpc earlier in the week after he told classmates he planned to attack his school, and asked the public to rely on official statements rather than spread unconfirmed rumours that could add to panic or encourage further threats.