Warsaw police said that 75 people were detained before the March set out at 2 p.m. and nearly 900 pieces of pyrotechnics were confiscated.

Spokesman Robert Szumiata said: “So far our police officers have secured numerous pyrotechnics, the carrying and use of which today has been banned by the decision of the Mazowieckie provincial governor.

“Among the items found during the search of some individuals were also knives, expandable batons, and a set of brass knuckles.”

Among those arrested were also several wanted on international arrest warrants.

Posting on X, Warsaw police said that those detained “included persons suspected of committing felonies, including drug possession, as well as minors carrying pyrotechnics, who, in accordance with provisions of the law, will have to be picked up by their legal guardians.”

Officers from the southern city of Bielsko-Biała who were sent to help uphold the peace also resuscitated a one-year-old boy who had stopped breathing.

But, according to police reports, the anniversary which has a history of outbreaks of violence by nationalist groups, passed by peacefully, with Warsaw city hall estimating that around 90,000 people attended, while the organizers said the attendance was over 100,000.