Evidence indicating that the Malaysia Airlines Flight 370 that went missing 10 days ago was sabotaged or hijacked was mounting after it emerged that the last message from the cockpit was spoken after someone had begun disabling one of the plane's automatic tracking systems.
The last words -- "All right, good night" -- were believed to have been spoken by the co-pilot.
"Initial investigations indicate it was the co-pilot who basically spoke," Malaysia Airlines CEO Ahmad Jauhari Yahya told a media briefing.
Captain Zaharie Ahmad Shah and his first officer Fariq Abdul Hamid are under scanner of the probe into the disappearance of the plane.
The last signal from the Aircraft Communications Addressing and Reporting System (ACARS) was received 12 minutes before the co-pilot's final words.
The officials are also looking at the possibility whether the plane -with 239 people on board including five Indians and one Indian-Canadian - had taken advantage of the busy airways over the Bay of Bengal and avoided suspicion of military radars.
Malaysia's defence and acting transport minister Hishammuddin Hussein said, "I can confirm that search and rescue operations in the northern and southern corridors have already begun.
Countries including Malaysia, Australia, China, Indonesia and Kazakhstan have already initiated search and rescue operations." A detailed map of the northern and southern corridors where the search operations were on was released today.
Malaysia got in touch with countries along the northern and southern corridors about the flight.
These countries include: Kazakhstan, Uzbekistan, Kyrgyzstan, Turkmenistan, Pakistan, Bangladesh, India, China, Myanmar, Laos, Vietnam, Thailand, Indonesia, Australia and France.
Australian was leading the search of the remote southern Indian Ocean for the missing plane.
Kazakhstan joined the search today in the farthest northwest section of the search area, taking the total number of countries involved in the operation to 26.
During the last 24 hours, Prime Minister Najib Razak has spoken to the Prime Minister of Australia and the Premier of China.
Malaysia's Ministry of Foreign Affairs has sent diplomatic notes to all countries involved in the search operation, Hishammuddin said.