Alarm bells are ringing yet again in China after another attack on school children.
The attack in the eastern province of Shandong happened despite a government vow to beef up security for schools and kindergartens across the country.
Police in the city of Zibo have detained 26-year-old Fang Jiantang, who reportedly confessed to the killings of three children and one teacher on Tuesday. Many others were injured, two seriously.
The state news agency, Xinhua, only released a brief English version of the story. Almost all online reports of the latest tragedy have now been deleted, perhaps for fear of more copycat attacks.
A spate of similar attacks from March to May had shocked the country. In April, a farmer in Shandong province injured five pre-school children and a teacher before burning himself to death.
The top leaders spoke of social tension as part of the cause and asked officials to do more to provide for school security.
The Ministry for Public Security and the Education Ministry scrambled for emergency measures to tackle the violent attacks.
More police officers have been assigned to patrol around school areas. Schools and kindergartens are supposed to have reviewed their security arrangements.
Some local police authorities have distributed instruments like steel pitchforks and pepper spray to security guards in schools.
But with schools on summer holiday, people have lowered their guard. And in some places, no adequate funds have been provided to implement the security measures.
China used to take pride in its low rate of violent crime but now it has to deal with it almost every day, leading many to ask what has caused the sudden surge of apparently random attacks.
The wave of violence has been portrayed as cases of "social revenge" in China.
Ji Jianlin, a professor of clinical psychology at Shanghai's Fudan University, says the incidents share some common features.
"The attackers all have grudges against society. They all try to take revenge by attacking the young and vulnerable," he says.
In part, the attacks reflect the social tension caused by rampant corruption and inequality. Some point to the lack of normal channels for ordinary people to air their grievances or to defend what little personal interests they may have.
But Prof Ji argues that there is a lack of social and psychological support in the rapidly changing society.
"In the past, China's workers used to have social support from the unions or women's associations. They used to provide quite adequate support. It's now quite weak."
This is especially true in smaller cities and towns. In a country where people used to be looked after from cradle to grave, the social change has not only left many Chinese without their traditional support mechanism but also pushed a large number of people into relative poverty.
And the income gap is widening further between the rich and poor.
This, coupled with a changed attitude towards life, has driven many to extremes in their desperate attempt to come to terms with the fast pace of change and the prevalent law of the jungle.
On top of that, there is still a stigma in Chinese culture about people needing psychological counselling.
Family members and society as a whole tend to conceal or shun those with mental health problems. This may partly lead to attackers failing to get help before they commit crimes.
Whatever the causes may be, the parents of the victims are paying a high price.