Why some schools survived

Lin also saw a Hope Project primary school, about 700 meters from the Beichuan Middle School, survive the disaster. There were three injuries but no fatalities at the second school, which had been donated by the Chinese Academy of Sciences.

"Its construction quality was ensured under the donor's supervision. But most of the collapsed schools had no such supervisory mechanism."

Said Lin: "If we educational officials hadn't left loopholes for corruption, the collapsed buildings could have been as solid as the primary school."

Gone in ten seconds

When the quake struck, the Fuxin No. 2 Primary School in Mianzhu City was leveled within 10 seconds, leaving 127 students dead. However, most of the surrounding residences remained standing, including those built in the 1960s.

On Sunday, more than 100 parents of children killed in the collapse marched downtown with placards bearing slogans and photographs of their children, questioning the construction quality and asking the authorities to investigate.

"They are heartbroken and demand an explanation. I can fully understand that," said Jiang Guohua, party secretary of Mianzhu City. "So I wouldn't evade them and walked up to them myself."

Jiang knelt before the bereaved parents, trying to persuade them not to go any further.

"I promise to produce a solution within a month. If the collapse was caused by construction problems, we will seriously deal with it according to the law. We will mete out due punishment to people accountable for that, as well as compensate the victims' families," Jiang said.

In Mianzhu City, eight schools would be examined by experts. "All of the experts were invited by the province from other cities to maintain justice," Jiang said.