– ‘Rigorous’ –
The incident sparked widespread outrage over alleged safety violations by Rui Hai and possible official collusion, and fears of pollutants contaminating the air and water of Tianjin, home to about 15 million people.
Thousands of tonnes of hazardous chemicals were stored at the site, officials have said, including about 700 tonnes of highly poisonous sodium cyanide, a white powder or crystal which can give off lethal hydrogen cyanide gas.
The warehouse was built within 600 metres (650 yards) of some residential buildings, despite a regulation mandating any hazardous material storage facilities must be at least 1,000 metres away.
Communist authorities and state-run media have sought to pin blame for the disaster on local individuals and officials, rather than systemic factors.
China’s powerful State Council, or cabinet, has vowed to conduct a “rigorous” investigation into the cause and has pledged it will publish the findings.
But independent Chinese reporting was quashed in the aftermath according to government censorship notices posted on China Digital Times, a US-based website.
“Websites cannot privately gather information on the accident, and when publishing news cannot add individual interpretation without authorisation,” read one notice it cited as sent out by the Cyberspace Administration of China.
Prosecutors said the officials they were investigating came from several government departments including transportation management, customs and work safety, and the president of a state-owned port company in Tianjin.
Industrial accidents are common in China, with corruption thought to be a key factor behind lax enforcement of safety regulations.
Less than two weeks after the Tianjin explosions, an explosion at a chemical plant in east China’s Shandong province killed one person and injured nine people.
The head of China’s work safety watchdog – a former vice-mayor of Tianjin – has been sacked after being put under investigation for corruption, state media said.