Mu Yongxian crouched in front of the rubble where Beichuan Middle School once stood and burned incense and paper offerings for two of his dead children. Mr Mu, a middle-aged construction contractor, lost his 19-year-old son and 17-year-old daughter in the disaster. While he has managed to accept the loss of his son with a measure of stoicism, he feels only seething rage for the death of his daughter. 'My son was a soldier. When he was killed in the earthquake, he was on duty and receiving military training,' Mr Mu said. 'I made no complaint about his death. But it's an utterly different story with my daughter. Her death, and the deaths of hundreds of her schoolmates, could have been avoided and were caused by man-made mistakes.' Mr Mu has obtained a copy of the blueprint for the school, which called for a very different structure from what was built. 'I collapsed and passed out for more than an hour after I studied the plan. When I woke up, I was so angry I even considered bombing the offices of the municipal and county governments. 'It's so obvious that if they followed the original construction design, the death toll... would not have reached as high as 1,500.' To gather more evidence, he went to the school ruins and inspected the collapsed structure. The steel bars used were far too thin and short for what was needed, Mr Mu said. 'How can you deny this is completely a 'tofu' project? The steel bars inside the cement were only 3cm long. The original design says they should be 35cm. The thickness of the bars was only 6mm, instead of the 14mm to 16mm the plan called for.' Armed with such evidence, Mr Mu and hundreds of other parents have tried to bring the extent of the situation to light. For a year they have lodged complaints and filed petitions at different levels of government, including the provincial government, the Mianyang municipal government and Beichuan county. 'They could not come up with any reasonable defence, but just kept shifting the responsibility to the strength of the quake. They said no building could have withstood it.' Mr Mu said he had been detained by police, who wanted to confiscate the blueprint. 'They offered me hundreds of thousands of yuan for the original design drawing. But I refused. I won't give it to them for all the wealth of the world.' He claims people close to the authorities have threatened him that having the school's original design amounted to possession of a state secret. But he could not be swayed; his anger kept him rooted to his mission. 'What I want to achieve is to make all my countrymen aware of what really happened and that the Beichuan Middle School was simply a tofu project. That, I believe, is the real cause of the deaths of hundreds of innocent young lives. 'A year has passed and I feel exhausted. But I will keep fighting until the end of my days,' he said. He is not alone. At least 20 parents of children who died at the school are calling for an open investigation into its collapse. 'I'm sure more than 2,000 parents will show up at the school on May 12 to voice our anger.' Justice is the last thing they can give their children. 'I have promised in my heart to my daughter that I will never give up seeking justice for her, as long as I'm still breathing. If I fail to get that done, I think I can't face her and I'm not worthy to be her father.'