The death toll in the powerful explosion at a chemical plant in eastern China climbed to 64 and injured 640 others injured on Friday as a number of people succumbed to their injuries.

President Xi Jinping ordered that the causes of the accident must be identified as early as possible.

The blast occurred on Thursday following a fire in a fertilizer factory in a chemical industrial park in Yancheng, Jiangsu province.

Executives of the chemical plant province have been taken into police custody.