Rescuers and machines clean up debris in the core blast area in Tianjin. Photo: Xinhua

Rescuers and machines clean up debris in the core blast area in Tianjin. Photo: Xinhua

Rescuers and machines clean up debris in the core blast area in Tianjin. Photo: Xinhua

Combined photo taken on August 21, 2015 (upper) and August 17 shows an automobile storage in the core blast area of Tianjin. Photo: Xinhua

Rescuers work at the core area of explosion site in Tianjin. Photo: Xinhua

A rescuer transports lighting facility to the core area of explosion site in Tianjin. Photo: Xinhua

Soldiers of a PLA chemical-defense unit work neutralizing sodium cyanide residue on the crushed vehicle wrecks in the zone of a massive chemical explosions in Tianjin. Photo: EPA

Rescuers clean up the debris at the blast site in Tianjin. Photo: Xinhua

Rescuers clean up the blast site in Tianjin. Photo: Xinhua