China explosions: Potent chemical mix behind Tianjin blasts
Authorities had earlier said that the warehouse contained calcium carbide, potassium nitrate and ammonium nitrate.
Calcium carbide is used in the production of PVC plastic, while the other two chemicals are used in producing fertiliser and dynamite.
There were unconfirmed reports that the warehouse contained 700 tonnes of sodium cyanide, stored in wooden boxes or iron barrels. The chemical is used in the mining industry, among other uses. Police on Saturday confirmed the presence of an unspecified quantity of it near the site.
(Tianjin disaster) Logistics company Ruihai stocked many hazardous materials