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

Photo taken on March 24, 2018 shows unmanned submersible "Hailong III" to be put into the sea for a deep sea testing from the Chinese research vessel Dayang Yihao (Ocean No. 1). The submersible completed a 1,690-meter-deep sea testing in West Pacific Ocean, March 25, 2018. (Xinhua/Chen Hao)