KUALA LUMPUR, Jan. 23 (Xinhua) -- Seabed Constructor, the vessel used by U.S. firm Ocean Infinity to locate the missing MH370 aircraft, has arrived at the search area and begun the search operation, said Malaysia's Department of Civil Aviation on Tuesday.

It said Ocean Infinity began its operation by launching the first autonomous underwater vehicle (AUV) at 02:55 Malaysia time (1855 GMT) on Monday.

Seabed Constructor brought with it eight such AUVs packed with sensors, detectors and cameras. Ocean Infinity said they are capable to comb some 1,200 square km per day, much faster than previous search efforts, which means they will finish the whole 25,000 square km search area within three or four weeks.

The Malaysian government signed a deal with Ocean Infinity earlier this month, which grants the U.S. firm 90 days to locate the missing aircraft on a "no cure, no fee" basis. If the wreckage or the black box were found, Malaysia will pay the firm up to 70 million U.S. dollars, subject to the size of the actual search area.

MH370, carrying 239 on board, went missing en route from Kuala Lumpur to Beijing on March 8, 2014.