PETALING JAYA, Malaysia - Malaysia Airlines Flight MH370 may have been tracked by the military's air defence radar to a spot 200 miles northwest of Penang, 45 minutes after the aircraft disappeared from civilian radar.
In a strange twist to the tale of the missing plane, Royal Malaysian Air Force chief Tan Sri Rodzali Daud said a review of the military's radar data recording showed an "aircraft" that was last plotted at 2.15am on Saturday flying at 29,500ft above sea level.
"I am not saying that this is MH370, we are saying that we are working with the experts to determine this aircraft's identity," Rodzali told reporters.
He said the discovery raised the possibility that MH370 could have turned back after all radio and civilian radar contact was lost.
A position 200 nautical miles roughly northwest of Penang would put the plane off Phuket and Phi Phi islands in Thailand or near Aceh in Indonesia.
The Boeing 777-200, bound for Beijing with 239 passengers and crew, took off at 12.41am Saturday, its subsequent disappearance described as an unprecedented aviation mystery that continues to grab global attention.
Rodzali said the Malaysian military radar records were being referred to the US Federal Aviation Administration (FAA) National Transportation Safety Board as well as the radar manufacturer for corroboration.
Military radar records from a neighbouring country also showed the presence of an aircraft on the same track, he added.
Asked why RMAF jets were not sent to intercept the aircraft as soon as it appeared on the military radar, Rodzali said the military radar operator tracked the trail of a civilian aircraft heading north.
"It was not classified as hostile. We only intercept and respond when the contact is classified as hostile."
Department of Civil Aviation director-general Datuk Azharuddin Abdul Rahman said civilian radar showed MH370 was cruising at 1.21am and the aircraft totally disappeared from the secondary radar at 1.30am.
"No communication...nothing at all," he said when asked whether the Aircraft Communication and Reporting System (ACARS) had been lost.
The primary radar used by the military tracks objects without identifying them while the secondary radar communicates with the aircraft using the onboard transponder to identify it and its position.
"The defence primary radar (data) was analysed the same day (Saturday) and is the reason why a search in the Straits of Malacca was conducted," said Azharuddin.
He said DCA investigators were scrutinising all radar tracking data and aircraft records.
Armed Forces chief Tan Sri Zulkefli Mat Zin said that when the Prime Minister instructed on Saturday for the search area to be widened, the military decided to review its air defence radar.
He said its data recordings showed a possibility that the aircraft made a turnback.
Zulkefli said the DCA radar data record in Kota Baru showed similar "blips" making the possibility of a "turnback" even higher.
"Can I take the risk of the aircraft turning back to the Straits of Malacca and not send some of my assets to that area?
"At the slightest possibility, I must respond," he said.
Asked why it took five days to reveal where the aircraft may have last been tracked on radar, acting Transport Minister Datuk Seri Hishammuddin Tun Hussein said the data needed to be verified.
"If the FAA and NTSB find that the raw radar data from the military is (MH370), I would announce it the next day," he said.
The search, which was originally focused over the South China Sea, has been expanded to include waters over the Straits of Malacca, with both areas covering 27,000sq nautical miles.
Azharuddin said it was possible for MH370 to have flown too low for radar to detect and that it could do so until it ran out of fuel.
He said the United Kingdom Aircraft Accident Investigation Branch and the aircraft engine manufacturer Rolls-Royce had asked to join the investigation, which he welcomed.