A gunman shooting randomly from a car killed four women and two men in the main square of the southern Polish city of Krakow on Saturday, officials said, before police shot and arrested the suspect.
Fifteen others were wounded including two police officers who were hurt - one of them seriously - in a shootout with the suspect, who police said wore "military-style" clothes and had military weapons.
Police said that the alleged gunman was a 24-year-old Polish citizen. "The only known perpetrator of the incident is in police custody," they added in a post on X. They did not mention a motive for the shootings.
Police said they started to receive reports at around 3 p.m. (1400 GMT) that an assailant had opened fire from a car and had shot randomly at people in the square in Poland's second-largest city, a popular tourist destination.
Unverified footage shared on social media showed people fleeing the scene as shots rang out and police sirens blared. Other video showed two people lying on blood-spattered paving stones and bystanders trying to resuscitate them. A third person lay motionless on the ground nearby.
"I saw shots being fired from the driver's side window, and smoke was coming out. I ran to the police station in the main market square; when I burst inside, it was full of people hiding on the floor," a man who gave his name only as Konrad, and witnessed the shooting, told news website Interia.
A 67-year-old man called Julek told Reuters that he saw a dark car appear suddenly before the driver started shooting at a group of people and drove off.
"If we had been two minutes earlier, we might have been shot," he said.
Katarzyna Cislo, a local police spokesperson, said: "The shooter was wearing military-like clothes and used military weapons. Many ... weapons and ammunition were found in his vehicle too."
Police spokesperson Andrzej Fijolek told private broadcaster TVN 24 that the assailant used an AR-15 rifle and that he had a firearms licence.
