Updated at 8:25 a.m. Eastern
A knife-wielding man attacked a kindergarten class of 4-year-olds in eastern China on Thursday, slashing 28 children in the third such rampage at a Chinese school in a month.
The three stabbings have been part of a series of school attacks in recent years, most blamed on people with personal grudges or suffering from mental illness, leading to calls for improved security. One sociologist said the attacks may happen in clusters, with one assailant triggering copycat attackers.
Five of the students injured Thursday were in critical condition in the hospital in Jiangsu province, said Zhu Guiming, an official with the propaganda department in Taixing city. Zhu said two teachers and a security guard at Zhongxin Kindergarten also were hurt in the attack, which happened early in the school day.
The suspect was identified as Xu Yuyuan, 47, who had been jobless since being fired from an insurance company in 2001, the official Xinhua News Agency said.
The attacker burst into a classroom at the kindergarten, waving an eight-inch knife and stabbing a security guard who tried to stop him, Xinhua said.
CBS News Correspondent Celia Hatton reports that Yuyuan then threatened to commit suicide before eventually surrendering as police rushed to ensure he'd be caught alive.
On Wednesday, a man broke into a primary school in Guangdong province's Leizhou city in southern China and wounded 15 students and a teacher in a . That attack came on the same day as another assailant was executed for killing eight children last month in stabbings that shocked China.
It was not known if Xu knew about the previous day's attack in Guangdong, but Zhou Xiaozheng, a sociology professor at Renmin University in Beijing, said these sorts of violent attacks often happen in clusters because one may trigger other copycat attacks.
"It's like suicide, which is another type of mental health problem that can spread in a community," said Zhou. "Normally, with these kind of violent events we hope the media won't blow them up too much. Because that tends to make it spread."
Hatton reports that China's state-controlled national media has been silent on the issue, focusing instead on the grand opening of the Shanghai World Expo. Still, word of the serial stabbings has spread on the internet and in local news circles and is rattling nerves.
A staffer at the No.1 Taixing People's Hospital said by telephone that the hospital had received some of those wounded in Thursday's attack. "The injured have been sent here one after another. The doctors are now trying their best to save them," said the worker, who like many Chinese officials refused to give his name.
In Wednesday's attack, in which a teacher stabbed fourth and fifth graders in their heads, backs and arms, Xinhua said the suspect suffered from mental illness and had been on sick leave since February 2006. He was now in police custody.
None of the victims in that case had life-threatening wounds, said the director of the command center at the Leizhou Public Security Bureau, who gave his name as Qin.
Wednesday was also the day that Zheng Minsheng, 42, was executed in neighboring Fujian province for the March 23 murders of eight children outside their elementary school as they waited with their parents for classes to start.
During his trial earlier this month, Zheng admitted to killing the children because he had been upset after being jilted by a woman and treated badly by her wealthy family.
Two weeks ago, a mentally ill man hacked to death a second grader and an elderly woman with a meat cleaver in southern Guangxi, and wounded five other people.
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