An emergency response team assembled by the Ministry of Transport (MOT) set out early Sunday from south China's Sanya Port in Hainan Province to the sea area where it is thought the missing Malaysia Airlines flight MH370 might have crashed.

The largest patrol vessel in South China Sea "Haixun 31" departured from Sanya on Sunday afternoon and is scheduled to arrive at the site on Tuesday afternoon, carrying 50 rescuers and facilities such as a maritime helicopter and sonar systems.

The "Haixun 31" will act as the commanding ship for organizing rescue and search efforts, according to the MOT.

Rescue vessel "South China Sea Rescue 101" is carrying 12 divers and salvagers, and will join another rescue vessel, "South China Sea Rescue 115," at the rescue site.

The latter ship is scheduled to arrive at the site on Monday afternoon, while "South China Sea Rescue 101" will get there on Tuesday afternoon, according to the MOT.

Rescue work remains challenging as there is no exact location of the possible crash site and it will take about two days for the rescue ship to reach the water, said Zeng Ying, leader of the emergency team.

"But we will try our best," added Zeng.

Sanya Port is about 700 sea miles from the possible site. Both of the rescue vessels have helipads which enable air search and rescue. "South China Sea Rescue 101" is 109.7 meters long, with 6,200 tonnes of full load displacement.

Meanwhile, another rescue vessel, "Tai Shun Hai" of China Ocean Shipping (Group) Company arrived at the possible site at 9 a.m. Sunday and started searching, according to the MOT.

The vessel has detected no clues yet after a 9-hour-search covering about 145 nautical miles, according to the MOT.

Another Chinese coast guard vessel also reported no findings of the missing plane and is expanding searching area with technical aids.

The state marine rescue center will coordinate with its Malaysian counterpart to arrange more vessels to conduct searching and rescue.

A Boeing 777-200 aircraft operated by Malaysia Airlines left Kuala Lumpur International Airport at 0:41 a.m. Beijing time on Saturday and was expected to land in Beijing at 6:30 a.m.

Contact with the flight was lost along with its radar signal at 1:20 a.m. Beijing time on Saturday when it was flying over the Ho Chi Minh air traffic control area in Vietnam.

The flight was carrying 12 crew members and 227 passengers, including 154 Chinese.