The explosion killed at least 139 people. The people detained worked for the company where the explosions happened and center around potential corruption.
A massive explosion in Tianjin, China killed more than 100 people earlier this month. Correspondent Frank Langfitt says the country's corruption and a lack of accountability have endangered lives.
Wednesday's massive explosion in Tianjin killed more than 100; then fire broke out, and more explosions followed. Now Chinese authorities are clearing the area over fears of sodium cyanide poisoning.