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By Own Correspondent| At least 20 children inside a Beijing primary school have been wounded following an attack by a male labourer, Chinese authorities have said.
The attack which took place at the Beijing No.1 Affliated Elementary School of Xuanwu Normal School, was carried out with a hammer, according to state-media outlet the Global Times.
Three of them suffered serious injuries but they were not thought to be life-threatening and are in a stable condition.
Jia, who was hired through a labor service company, worked at the school as a contract maintenance worker.
"The children were attacked while they were doing exercises on the school running track".
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However, all the children are receiving hospital treatment and an investigation has been launched. According to the school's website, it has 2,537 students and 199 teaching staff.
"I was terrified", said an elderly man who gave only his surname, Xie. In the clip, the head teacher confirms that the attack was carried out by a former employee and occurred on the school's first floor in a number of different second grade classrooms. "It would be fine if he attacked us old people, but kids are young and innocent, and they don't know how to defend themselves".
Two children were also stabbed to death outside a Shanghai kindergarten in June, while nine children died in a knife attack at a school in Shaanxi province in April.
Many schools in China have beefed up security following violence against students and family members.
In November, a driver rammed his vehicle into a group of children crossing a street in front of an elementary school in northeastern Liaoning province, killing five people and injuring at least 19.