Malaysian PM says missing plane systems deliberately 'disabled'

The Malaysian prime minister has said that new information tells with a "high degree of certainty" that communications of the plane that went missing a week ago was disabled just before the aircraft reached the east coast of Malaysia.

Prime Minister Najib Razak said in the news conference on Saturday that the movements of the aircraft were "consistent with deliberate actions" by someone on the plane. 

According to satellite and radar evidence, he said, the plane then changed course and could have continued flying for a further seven hours.

He said the "movements are consistent with the deliberate action of someone on the plane".

The plane disappeared a week ago with 239 people on board. The Kuala Lumpur-Beijing flight last made contact with air traffic control over the South China Sea to the east of Malaysia, about one hour after take-off.

Satellite signals continued to be picked up from the plane some seven hours after it lost radar contact. Razak said the authorities were now trying to trace the plane across two possible corridors; from the border of Kazakhstan and Turkmenistan through to northern Thailand and south from Indonesia to the southern Indian Ocean.

The investigation, he said, had "entered a new phase", and the search of the South China Sea had been discontinued.

Addressing reports that the plane had been hijacked, he said only "we are still investigating all possibilities as to what caused MH370 to deviate".

Flight MH370 has 239 people on board and more than 150 of them are Chinese.

There has been no sighting of the Boeing 777 since it disappeared from the radars and no debris has been found.

The search operation includes 57 ships and 48 aircraft and covers the Strait of Malacca, the Indian Ocean and the Andaman Sea. Razak said the search area would no longer include the South China Sea.