LONDON: In 2012, a Taliban gunman shot her in the head for advocating education for girls in her native Pakistan. On Friday, Nobel Peace laureate Malala Yousafzai completed her schooling in Britain, calling the achievement "bittersweet", reports AFP.

"Today is my last day of school and my first day on @Twitter," she wrote on her newly opened account, which gained more than 134,000 followers in three hours.

Yousafzai, who will be turning 20 this month, had been attending a school in the city of Birmingham where she was treated after the shooting in October 2012.

After blogging and campaigning for girls' education in her native Swat valley, she was shot as she rode back to her village on a bus after taking an exam.