China covers 628,000 sq km searching for MH370

A sailor aboard Chinese navy's amphibious landing vessel Jinggangshan scans the ocean in search for the missing Malaysia Airlines flight MH370, in southern Indian Ocean, on April 13, 2014. (Xinhua/Bai Ruixue)

Chinese vessels have covered about 628,000 square kilometers in the southern Indian Ocean by midday Monday in search of the missing Malaysian flight MH370, said the China Maritime Search and Rescue Center. [Special coverage]

The center had also mobilized 64 merchant ships for assistance, which covered 173,000 square kilometers.

No objects related to MH370 have been found, the center said.