'It emerged that (Tim) Kretschmer had been suffering from depression, even attending a clinic and receiving medication for the condition.
The 17-year-old had far from excelled at Albertville. His parents – his father Joerg was a wealthy owner of a packaging firm employing 150 people – had removed him from the state secondary in 2007 and sent him to a private school. His grades were poor and teachers were unimpressed.
The Kretschmers hired a tutor. She felt the boy had problems. "He was a really strange boy – introverted and closed," she told German newspapers. "But he did love his cat."
Kretschmer tried sport – especially table tennis – but wasn't very good. Over the years he became more and more interested in just two passions: violent computer games and guns. The teenager was obsessed with Counter-Strike, a 'shoot 'em up' game in which special forces have to kill terrorists to win. He was good, his few friends said. He was also, they added, a fine shot.'
Story here