A law professor has been stabbed to death by one of his students, according to the Chinese news agency Xinhua. Cheng Chunming was killed by a 22-year-old student at the China University of Political Science and Law. The man reportedly burst into a classroom with a kitchen knife while Professor Cheng was lecturing students and stabbed him twice in the neck. The killer subsequently surrendered to police. The 19 students who witnessed the attack have been given counselling by the university.