Beijing's Zhongguancun No 2 Primary School issued a statement on Tuesday, insisting that an incident involving a fourth-grade student was not bullying.

The student had a wastepaper basket from a bathroom thrown at him and was mocked by classmates, leading to him suffering acute stress disorder.

"We feel terribly sorry and apologize sincerely for the hurt brought to students and parents involved in the incident," the school said in the statement, adding that it will deal with the incident objectively and fairly, while making efforts to forge harmonious relationships among students on campus.