The area has been expanded from 50 nautical miles from where the plane had disappeared - over waters between Malaysia and Vietnam - to 100 nautical miles (185km).
Indians on board have been identified as Chetna Kolekar, 55, Swanand Kolekar, 23, Vinod Kolekar, 59, Chandrika Sharma, 51, and Kranti Shirsatha, 44.