A 22-year-old man detonated an improvised explosive device (IED), or homemade bomb, at a nursery in the eastern Chinese city of Xuzhou, killing nine, including the assailant, and injuring about 65 others.

“Local officials revised the death toll from seven to eight late on Thursday, saying that two people died at the scene, and another six died later in hospital,” reports the Telegraph.

The news outlet notes that the incident is the latest in a spate of attacks mainly carried out by disgruntled workers targeting nurseries and other schools and killing and wounding scores of children.

Citing a police count, National Public Radio (NPR) adds that up to 65 people injured, including four in critical condition.

The explosion occurred Thursday afternoon in eastern China’s Xuzhou, Jiangsu province.

“Most attacks in China – where gun controls are strict – are carried out by assailants using knives or homemade explosives,” acknowledges the Telegraph.

Local law enforcement revealed the explosion did not harm any students nor teachers, but National Public Radio (NPR) notes that “images taken in the aftermath of the blast showed children and adults, their clothing burned, strewn about at the gate of the kindergarten in pools of blood.”

Through the DNA evidence, Chinese authorities have identified the suspect as surnamed Xu. He detonated the IED at the building’s front gate.

“They [local police] also said the man had dropped out of school because of an autonomic nervous system disorder. Symptoms include depression, anxiety, dizziness and problems with basic bodily functions,” points out the Telegraph.

Police discovered the words “death,” “kill,” and “extinct” carved on the walls of Xu’s house.

The Telegraph reports:

Police also found materials used to make bombs in the property, and said that the man, who was surnamed Xu, had lived and worked near the nursery [his target]. They also said the man had dropped out of school because of an autonomic nervous system disorder. Symptoms include depression, anxiety, dizziness and problems with basic bodily functions.

The motive behind the crime remains unknown.

“Official media said on Thursday that ‘gas cylinders’ may have exploded,” points out the Telegraph. “Safety standards are lax in China.”

In the wake of the attack, China’s Ministry of Education escalated security at all schools.