A gunman killed six people Monday in a German youth welfare centre for mothers and their children in what police said was a likely “family tragedy”, before the male suspect and a female companion were arrested. The deadly shooting spree sparked a major police operation in the northern city of Stade, about 50 kilometres from Hamburg. The six people killed were all adults, among them one who succumbed to their injuries in hospital, while another person was wounded and in stable condition, a police spokesman told AFP.