A pupil slit his teacher's throat as he was marking papers - because he had confiscated the boy's mobile phone.
The student had been caught playing with his phone by his teacher Sun Wakang during a chemistry lesson at a school in in Fuzhou, eastern China's Jiangxi province.
The following day, the pupil - referred to only as Lei in news reports - went to father-of-one Mr Sun's classroom and slit his throat from behind as he worked.
The 32-year-old died at the scene as the student fled. He has since turned himself in to police in Shanghai.
Mr Sun, who had worked as a chemistry teacher at Linchuan No. 2 Middle School for five years, had taken the student's mobile phone after the young boy had used it during a lesson, but it had been returned at the end of the day. Despite this, Lei attacked Mr Sun.
SUBSCRIBE AND FOLLOW PARENTS
Get top stories and blog posts emailed to me each day. Newsletters may offer personalized content or advertisements. Learn more