Sound of gunfire

The evacuation was conducted under fire in some places, in particular near key infrastructure projects that were being fought over by the rebels and the government forces.

Aden has seen hundreds of people killed in what at times has been street-to-street fighting. Timing was of the essence to pick up the foreigners and, while any period of the day was dangerous, the fighting seemed less intense in the morning.

The Linyi docked at 10:15 am on Thursday, and although the fighting had subsided, the sound of gunfire and mortar explosions could still be heard.

Jiang Guoping, an officer with the PLA navy's 19th convoy fleet, told China Central Television, "We're learned that fire is exchanged more intensively in the afternoons and evenings."

Jiang said the evacuation had to be conducted quickly before the fighting escalated in the afternoon.

As if to confirm the danger, just 35 minutes after the evacuation began, a mortar shell explosion could be clearly heard nearby.

Zhou Yongsheng, a professor at the China Foreign Affairs University, said the success of the evacuation highlights the increasing experience of China's diplomatic missions and the growing international support for the country's humanitarian efforts.

Xinhua contributed to this story.