The Chinese navy fleet conducting escort missions in the Gulf of Aden and Somali waters are pictured in this Dec 26, 2014 file photo. [Photo/Chinanews.com]

Beijing said on Monday that 122 Chinese citizens have been evacuated from Yemen, and the approximately 400 people remaining are expected to be evacuated soon.

The ongoing Yemen crisis has triggered concerns from the international community as more countries evacuated their nationals from the conflict-torn nation.

"Up to now, 122 Chinese citizens have been evacuated safely from Yemen to Djibouti, and the Chinese embassy in Djibouti is energetically assisting them for an early return to the motherland," Foreign Ministry spokeswoman Hua Chunying said in a daily news conference in Beijing.

The evacuation was made under the emergency-response coordinating efforts of the Foreign Ministry, the Ministry of National Defense and the Chinese embassies and consulates in Yemen, Aden and Djibouti, she said.

The Ministry of National Defense announced on its website earlier Monday that a People's Liberation Army navy fleet, which had been undertaking an escort mission in the Gulf of Aden and Somali waters left for Yemen on Sunday for the evacuation mission in accordance with an overall deployment.

Hua Chunying noted that since March 26, the security situation in Yemen has ""deteriorated gravely" and the Chinese government "places great priority on the safety of Chinese citizens and organizations based in Yemen and an orderly evacuation was started immediately".

On the Chinese citizens remaining in Yemen, the spokeswoman said Chinese Ambassador to Yemen Tian Qi and necessary embassy and consulate staff in the country "have dedicated themselves to stick to their duties and remained in close contact with the relevant parties".

The diplomatic staff there is "sparing no effort in arranging the early and orderly evacuation of the rest of our citizens", which is estimated to be around 400 people, Hua said.

China would also like to "extend sincere appreciation to the remarkable assistance offered by relevant parties in Yemen and Djibouti", the spokeswoman added.

On Sunday night, a Pakistani plane moved 503 of its nationals out of Yemen, Xinhua news agency reported.