Russian President Vladimir Putin, who has launched a full-scale vicious invasion of Ukraine, stopped socialising aged 11 after setting himself a serious goal. Born into a working-class Saint Petersburg family, Putin himself admitted that he was badly-behaved "hooligan" as a youngster. In an interview appearing in his 2000 book, ' First Person ', one of his teachers, Vera Gurevich said Putin "abruptly changed" when he was 11-years-old. She told the book: "[Putin] himself changed very abruptly in the sixth grade. It was obvious he had set himself a goal. "More likely he had understood that he had to achieve something in his life."