DHAKA: The authorities are cancelling air and ship searches for the missing Malaysia Airlines plane and have switched to a larger underwater operation that will cost 60 million Australian dollars and could take at least eight months to complete.

Australian prime minister Tony Abbott said it was ‘highly unlikely’ that floating debris would be found, and the operation would now focus on an underwater search across an area of the Indian Ocean spanning 700km by 80km.

Searchers will continue to use an unmanned Bluefin-21 submarine operated by the United States Navy, but will also look to hire private contractors to deploy towed side-scan sonar equipment to scan the seabed for wreckage.

Unlike the Bluefin-21, which emerges after each mission to have its data downloaded, the side-scan equipment can scan and produce imagery as it is towed, reports The Straits Times.

BDST: 1431 HRS, APR 29, 2014