Five young children have been hurt at a school in north-eastern China after a man attacked them with a hammer before killing himself

It was the third such incident in China in as many days. The man, said to be a local farmer, grabbed two children before setting himself on fire at the pre-school in Shandong province's Weifang city. The children were pulled to safety, and all five - plus an injured teacher - were said to be stable in hospital. China is reeling from a spate of apparent copy-cat attacks in schools. Previously, 28 children - most of them aged around four - and three adults were attacked by an unemployed man wielding a knife at a nursery school in Jiangsu province, eastern China. Five of the children were taken to hospital in a critical condition. And a day earlier, some 15 pupils and a teacher were wounded by a former teacher - who was on sick leave - at their primary school in Guangdong province. Recently a doctor convicted of stabbing eight children to death in Fujian province in March was executed. Since a spate of attacks in 2004, many schools in China have employed professional guards but the latest incidents have led to public calls for increased security in schools. The education ministry ordered all schools to upgrade their security facilities, as well as teach students about safety and ensure young children are escorted home. But such measures are expensive and in reality there is little that can be done to prevent such acts of violence. The incidents have also sparked a debate about the motives of the killers, with some suggesting that rapid social change and growing unemployment has led to an increase in psychiatric illnesses.