Without transparency, probe into Tianjin blasts will yield few answers

Premier Li Keqiang's pledge to investigate the explosions that devastated Tianjin with the loss of so many lives, and to punish those guilty of dereliction of duty, are commendable. But they are a textbook response to one of the worst examples of a dismal record of industrial safety that exacts a terrible price for China's economic progress. Ultimately more important is his promise of "open and transparent information disclosure". On past experience that is not to be taken for granted amid a culture of opacity and secrecy that all too often serves official and vested interests. But it is paramount that an investigation reveals without fear or favour all the circumstances of the disaster.

Only then can the investigation comply with President Xi Jinping's direction for handling the aftermath - that lessons should be learned and that leaders at all levels must place work safety at the top of their agendas.

More than five days after the explosions, followed by a conflagration that destroyed part of the storage area in Tianjin's port, rumours and questions about the causes and background abound, but there are few answers. Indeed, it seems officials have devoted more time to tracking down rumour-mongers than searching for and revealing the truth.

Reports that hundreds of tonnes of highly poisonous sodium cyanide were stored at a warehouse, quickly removed from a state media website soon after the blasts, have now been confirmed. It is common knowledge how dangerous the chemical can be, especially when large shipments are constantly being delivered, warehoused and shipped. So many basic questions about the operation remain unanswered, even down to the amounts stored. Why and under what conditions was the company that took delivery of the cyanide at the warehouse allowed to handle a huge volume in such a location? Why were homes built within 600 metres instead of the minimum of 1,000 metres stipulated in regulations? In this regard, what steps were taken to mitigate the risk? Last, but far from least, what is the environmental aftermath? Already, environmentalists are warning it is much worse than reported.

The textbook response of a nationwide safety check on these kinds of hazards may be under way. But that, and punishment of those held to account, are not enough. The authorities must get to the bottom of what happened, learn the lessons from it and implement them - openly and transparently.