The new law passed by the Standing Committee of the National People's Congress says that all schools must now be built to higher earthquake standards than other public buildings, Xinhua News Agency reported late on Saturday.

School safety has become a major concern in China after May's 7.9-magnitude quake killed nearly 70,000 people in Sichuan province and brought down 7,000 schools. Often schools were the only buildings in the area to fully collapse.

The new law - which takes effect next May - also requires schools to teach students about earthquake safety and response, Xinhua said.

The report did not say what penalties would be imposed if the laws were broken.

On Friday, the China Daily newspaper quoted a government official saying many of China's elementary and middle school buildings were structurally unsound, with as many as 20 percent in one province considered unsafe.

The school collapses have become a sensitive political issue, with parents - many of whom lost their only child in the quake - staging protests demanding investigations. Many of the parents say they have also been subjected to intimidation and financial inducements in attempts to silence them.

State media reported on Saturday that three moderate earthquakes hit China's southwestern region on Friday, injuring 19 people and forcing the evacuation of thousands of homes. -- AP