Navy vessel 872 with strong underground searching capacities has left for the southern Indian Ocean and is expected to arrive on May 10, said Wang Zhenliang, deputy head of the center, on Friday.

The search will face more complicated situations in the southern Indian Ocean, Wang said.

China has sent a total of 18 naval vessels, 13 planes, and used 21 satellites in the search operation, said Chinese Foreign Ministry spokesman Qin Gang on Thursday.

Malaysia Airlines said in a press release on Thursday that as there is still no trace of the missing flight MH370, the search operation in the southern Indian Ocean is moving to a new phase.

Its Chief Executive Officer Ahmad Jauhari Yahya said on Thursday in a statement that all of the company's Family Assistance Centers around the world would be closed by May 7, 2014, and Malaysia Airlines would keep in close touch with the families on the news updates through various ways.

Flight MH370 went missing on March 8 en route from Kuala Lumpur to Beijing.