An unmanned Chinese submersible has set a new national record by sinking 10,767 meters below sea-level in the Mariana Trench in the West Pacific.

The Chinese Academy of Sciences said the vehicle -- called the "Haidou-1" -- collected biological samples at different sea levels, including some unknown species, over the past couple of months.

In 2012, a Chinese manned submersible, the "Jiao Long", reached the depth of 7,000 meters in the Mariana Trench.