Investigators have said they're trying to discover a motive for the shocking mass-shooting in Sweden but currently believed the gunman acted alone. Despite not being identified, it's revealed he also legally changed his name eight years ago - a move that surprised his family. Eleven people were killed in the shocking attack at Risbergska School in Örebro before the man turned the gun on himself. Relatives added: 'He's really a loner. He used to have a friend he hung out with a lot, but not now.