Hours after the destruction in the northern Chinese port city, the cause of the blast on Wednesday night remained unclear. The terrifying explosions ripped through warehouses with hazardous chemical materials, shaking buildings more than two miles away and shooting fireballs across the sky.

Tianjin is a city of more than 13 million people. A chemical odor hangs in the air. Among the 50 people confirmed dead are twelve firefighters. More than 500 injured are hospitalized, of which 71 in critical condition. Dozens of firefighters are still missing.

Yesterday, August 13, local authorities suspended firefighting because of a lack of information concerning the "dangerous goods" stored at a warehouse located at the heart of the blast.

The explosion originated at a warehouse of Tianjin Dongjiang Port Rui Hai International Logistics. The company transports dangerous chemicals. Its executives were taken into custody.

The destructive force of the blasts tore into Tianjin, smashed buildings and mangled shipping containers. The first explosion was terrifying, but the second was more powerful producing the equivalent of 21 m.tons TNT or a magnitude 2.9 earthquake.

The environmental group Greenpeace said in a statement, it feared the danger was not over and expressed concerns that certain chemicals would continue to pose a risk to the Tianjin's residents as these threatened human health on contact. TDI and Ca(C2) reacted violently with water and reactive chemicals, with great risk of explosion, and that would present a challenge for firefighters, with rain forecast for today (August 14), which was a major hazard.

Royal Caribbean Cruises said in a statement on the situation that the company were currently monitoring it, and were in regular contact with Tianjin's port authorities. Still, there were no changes to the scheduled departure of Mariner of the Seas on Saturday, August 15. The cruise ship is scheduled for a 4-night voyage departing Tianjin on Saturday, with a port of call Fukuoka, Japan.