Gunman kills six and injures 15 in Krakow, Poland

A gunman killed six people and wounded 15 others in the Polish city of Krakow, according to reports carried by the Economic Times. Details about the attacker, the exact timing, and the circumstances behind the shooting were not available in the material provided. Further information on the victims, any suspects, and the motive would be needed to complete an accurate account. Please share the full article text so a fuller four-to-five sentence summary can be written.