Published: May 12, 2010 11:36 AM EDT

BEIJING (AP) - Seven children and a teacher are dead in another savage school attack in China, and reports indicate the teacher and the attacker may have known each other.

A local official and state media report the killer returned home after the attack on the kindergarten and committed suicide. The official Xinhua News Agency reports the victims are five boys, two girls and the teacher.

Xinhua put the number of wounded at 11 children and one adult and said two children are in serious condition.

The attack occurred despite a countrywide boost in security at schools. It's the fifth major assault at a school since late March, sparking security fears among parents, officials and educators.

The city government where the attack occurred says about 2,000 police officers and guards have been detailed to provide extra security.