A knife-wielding man killed nine middle school students and injured 10 others as they returned home after school in Yulin City in northwestern China’s Shaanxi Province on Friday.

The latest number of casualties was updated by the local police department on Saturday. Seven students were killed according to Friday's report.

The death toll has since increased as two more students died from their injures.

The nine deceased include seven girls and two boys, Xinhua News Agency citing local police, but did not mention the age of students being attacked.

The 28-year-old suspect was detained and the other 10 injured children are still receiving treatment in the hospital, according to the Mizhi County authorities.

He told police that he was bullied by classmates when he was in middle school, which caused his hatred towards students and resulted in today’s attack.

The attack happened at 18:10 local time and an investigation into the incident is underway.