The boy suspected of killing his teacher in Fuzhou, Jiangxi province, surrendered to police in Shanghai on Monday morning and has been handed over to Jiangxi authorities, according to the public security bureau of Shanghai's Pudong New Area.
The 17-year-old student, surnamed Lei, called the police at around 7 am on Monday on Shangnan Road in Pudong and said he stabbed his teacher to death in Linchuan No 2 High School in Fuzhou on Saturday.
Lei, who is in the final year of school, stabbed the teacher, surnamed Sun, on the neck with a fruit knife in the teacher's office.
Sun, born in 1981, died on the spot, and Lei fled.
The teacher took away Lei's mobile phone the day before because the teenager was only minding his phone in class, which is against classroom rules, according to the school.