Authorities say investigations focus on 28-year-old suspect and his 24-year-old brother who were motivated by 'radical Islamist' convictions to plan attack with homemade explosive

Wednesday's rampage by German-Armenian man on a popular shopping street left a schoolteacher dead, nine wounded

Authorities say they are investigating a suspicious object in Breitscheidplatz; local newspaper reports 2 Syrians with explosives experience detained