China's unmanned submersible "Hailong III" completes deep sea test

Unmanned submersible "Hailong III" is fixed on the deck of its carrier, the Chinese research vessel Dayang Yihao (Ocean No. 1), after a dive in West Pacific Ocean, March 25, 2018. The submersible completed a 1,690-meter-deep sea testing on Sunday. (Xinhua/Chen Hao)