Report on MH370 points at 4-hour gap before search for plane

Air traffic controllers failed to notice for 17 minutes that the ill-fated Malaysian jet had gone off the radar and did not activate a rescue operation for nearly four hours, according to a preliminary report on the mysterious disappearance of MH370 released on Thursday.

The two details were outlined in the much-anticipated report by Malaysia's Transportation Ministry released to the public nearly two months after the Malaysia Airlines Boeing 777-200 disappeared.

"Over a month after the aircraft departed Kuala Lumpur International Airport, its location is still unknown," said the report dated April 9.

The report was earlier sent to the International Civil Aviation Organisation, the UN body for global aviation.

At 1:21 am (local time) on March 8, the Malaysia Airlines plane -- carrying 239 people -- including five Indians -- disappeared from radar en route to Beijing.

It was not until 17 minutes later at 01:38 am that air traffic control in Ho Chi Minh, Vietnam, asked its Malaysian counterpart where the plane was.

Then came a nearly four-hour gap -- from the time when officials noticed the plane was missing to when the official rescue operation was launched.

Kuala Lumpur Rescue Coordination Centre (KLRCC) was activated at 05:30 (local time) after all effort to communicate and locate the aircraft failed.

The report gives no explanation for what happened during those four hours, other than to say that Kuala Lumpur contacted Singapore, Hong Kong and Cambodia.

The report recommended that the ICAO consider introducing a system for tracking commercial aircraft in real time.

"There have now been two occasions during the last 5 years when large commercial air transport aircraft have gone missing and their last position was not accurately known," the transport ministry said.

"This uncertainty resulted in significant difficulty in locating the aircraft in a timely manner," it said.

The report was accompanied by audio recordings of verbal exchanges between the cockpit of the plane and air traffic controllers and documents pertaining to the cargo manifest.

Malaysia believes the flight was deliberately diverted by someone on board and that satellite data indicates it crashed in the Indian Ocean, west of the Australian city of Perth.

The Malaysian government has so far been tight-lipped about its investigation into the disappearance of the Malaysia Airlines jet, adding to the anger and frustration among relatives of the passengers.