The shooter from Krakow killed a family before the attack.
According to Polish authorities, 24-year-old Michal O. first shot his sister and parents, and then opened fire on bystanders and police officers with an AR-15 rifle.
Previously, he had not come to the attention of law enforcement officers and had a gun permit. The head of the Polish Ministry of the Interior said that the attacker acted alone and was a fan of extreme right-wing ideas.
One of the neighbors said that the man had been causing her concern for a long time: he often walked around wearing a mask and hood up. According to the latest data, six people were killed and another 15 were injured.