NANJING -- Eight people were killed and 17 others injured in a knife attack at a vocational school in Yixing city, East China's Jiangsu province, on Saturday, said local police authorities.

The attack took place at around 6:30 pm at the Wuxi Vocational Institute of Arts and Technology. The 21-year-old suspect, surnamed Xu, was caught at the scene and he confessed to his crime, according to a statement released by the public security bureau of Yixing.

According to the police, Xu, a graduate of the school this year, returned to the school to vent his anger for not receiving his graduation certificate due to failing exams and for dissatisfaction with his internship pay.

Rescue efforts are underway, and police are further investigating into the case.