AFP, Tianjin :Hundreds of tonnes of highly poisonous cyanide were being stored at the warehouse devastated by two giant explosions in the Chinese port of Tianjin which killed 112, a senior military officer said today.The comments by Shi Luze, chief of the general staff of the Beijing military region, were the first official confirmation of the presence of the chemical at the hazardous goods storage facility at the centre of the blast.The disaster has raised fears of toxic contamination and residents and victims’ families hit out at authorities for what they said was an information blackout, as China suspended or shut down dozens of websites for spreading “rumours”.Nearly 100 people remain missing, including 85 firefighters, though officials cautioned that some of them could be among the 88 unidentified corpses so far found.More than 700 people have also been hospitalised as a result of Wednesday’s blasts — which triggered a huge fireball and a blaze that emergency workers have struggled to put out since then, with fresh explosions yesterday.Shi, who is a general, told a news conference that cyanide had been identified at two locations in the blast zone. “The volume was about several hundreds of tonnes according to preliminary estimates,” he said.A military team of 217 chemical and nuclear experts was deployed early on, and earlier Chinese reports said 700 tonnes of sodium cyanide were at the site.Officials have called in experts from producers of the material — exposure to which the US Centers for Disease Control says can be “rapidly fatal” — to help handle it, and the neutralising agent hydrogen peroxide has been used.Authorities have repeatedly sought to reassure the public, insisting that despite the presence of some pollutants at levels above normal standards, the air in Tianjin remains safe to breathe.Chinese Premier Li Keqiang arrived in Tianjin today afternoon to direct rescue efforts, a move often made after major disasters in the country, official media reported.Pictures showed the Communist Party number two within a kilometre (mile) of the blast site, dressed in an ordinary white shirt and not wearing a mask.But the official Xinhua news agency reported late yesterday that cyanide density in waste water had been 10.9 times standard on the day following the explosions. It has since fallen but was still more than twice the normal limit.Angry relatives of the missing firefighters stormed a government news conference Saturday to demand any information on their loved ones. The death toll includes at least 21 firefighters – making the disaster the deadliest for Chinese firefighters in more than six decades.