How did this happen?

At least 123 people were killed after a massive explosion ripped through a chemical storage facility in Tianjin port earlier this month. Now residents want to know went wrong

Mystery still surrounds the massive chemical explosion at Tianjin port, which killed at least 123 people earlier this month.

At the center of the storm is Tianjin Dongjiang Port Rui Hai International Logistics Co, which stored toxic chemicals at the blast site. Residents living close to the storage facility have described it as an "arsenal".