Malaysian authorities have CCTV recordings of the two passengers who were said to have used false passports to board the missing Beijing-bound Malaysia Airlines flight MH370.
Department of Civil Aviation director-general Azaruddin Abdul Rahman said on Sunday there were only two such passengers, not four as earlier reported by the media.
"We have CCTV recordings of them from check-in until boarding and departure," he said at a press conference on Sunday.
The recordings have been handed over to investigators.
Earlier, two men - an Italian and an Austrian - had confirmed that they were not on the flight despite their names appearing on the manifest. Their passports were reported stolen in Thailand up to two years ago.
Mr Azaruddin also confirmed that five passengers did not board the MH370 flight, and their baggage were removed from the cargo. He did not say why they did not board the plane.
Malaysia's Air Force chief Rodzali Daud said a review of the military radar showed a possibility of an air turn back. This meant that the plane had deviated from its course to turn to come back on the same flight path.
He said this finding was corroborated by the civil aviation radar, and they were also checking with the radar of other countries.
He said one reason could be that the pilot was trying to return to Kuala Lumpur International Airport from where the plane had taken off 50 minutes earlier. Normally, this happened if the pilot was unable to proceed as planned, and he would normally report this to air traffic control.
But there was no such distress call from this plane, he said.
"We are trying to make sense of this," he added.
He declined to say how far the plane had turned back before it disappeared.
Earlier, the authorities had said the plane was last on the radar at approximately 120 nautical miles off Kota Baru, in the South China Sea, in the airspace bordering Vietnam. Malaysian air traffic control had just handed over control to the Vietnamese authorities when they lost contact.
As a result of this possible around turn by the plane, the search has been widened to the Straits of Malacca especially in the area around Penang.
The Armed Forces chief Zulkifeli Mohd Zin said there are now 22 aircraft and 40 ships searching for the missing plane. This includes assets deployed by Singapore, Thailand, the Philippines, China, Vietnam and the US, as well as Malaysia.
Malaysia was also conducting a land search using helicopters.
Malaysia Airlines chief executive Ahmad Jauhari Yahya said there are no plans to ground their other Boeing 777-200 as it has proven to be a safe aircraft.
He confirmed that flight MH370 was operated using a plane that had its wing clipped in an accident some years ago, but it had been repaired and certified safe by Boeing.
Malaysia Airlines flight MH370 lost contact with Subang Air Traffic Control 50 minutes after departing KLIA at 1241am Saturday.
It was due to land in Beijing at 630am, and had enough fuel to fly up to 830am. The plane did not issue a distress signal nor was there bad weather when it disappeared.
The flight was carrying a total number of 239 passengers and crew - comprising 227 passengers (including 2 infants) and 12 crew members.
There were 15 nationalities on board, the majority Chinese nationals and Malaysians. No Singaporeans were on board.
Flight MH370 was operated on a Boeing 777-200 aircraft, a codeshare with China Southern Airlines. The plane was 11 years 10 months old.
Malaysia said the search would go on round the clock until a decision was made to call it off.
The next press conference is scheduled at 3pm.