Malaysia's Department of Civil Aviation (DCA) Director General Azharuddin Abdul Rahman arrives at the hotel where relatives of the passengers of missing Malaysia Airlines flight MH370 have been staying, in Putrajaya outside Kuala Lumpur April 3, 2014. Malaysia's prime minister visited the Australian search base for missing Flight MH370 on Thursday as a nuclear-powered submarine joined the near-four week hunt that has so far failed to find any sign of the missing airliner and the 239 people on board. REUTERS/Samsul Said (MALAYSIA - Tags: DISASTER TRANSPORT)