INTERPOL is investigating more suspect passports used to board the missing Malaysia Airlines flight after it was confirmed two passengers were travelling with stolen documents.
The development came as search teams salvaged what could be a door from the Boeing 777 in the sea off Vietnam amid fears that the airplane may have disintegrated mid-flight.
Officials also said they thought flight MH370 from Kuala Lumpur to Beijing with 239 people on board may have started to turn around before disappearing on Saturday.
Malaysian civil aviation chief Azharuddin Abdul Rahman said: “On the possibility of hijack, we are not ruling out any possibility.”
Interpol said it knew about the stolen passports, but it had received no inquires relating to them from the time they were taken two years ago.
Officials said Austrian man Christian Kozel and Luigi Maraldi, an Italian, whose passports were stolen in Thailand, were not on the plane, despite being listed as passengers.
CCTV footage of the passengers posing as them is being studied.
An Interpol spokeswoman said a check of all documents used to board the plane had revealed more “suspect passports” that were being further investigated.
The organisation’s Secretary General Ronald Noble said: “Whilst it is too soon to speculate about any connection between these stolen passports and the missing plane, it is clearly of great concern that any passenger was able to board an international flight using a stolen passport listed in Interpol’s databases.
“This is a situation we had hoped never to see. For years, Interpol has asked why should countries wait for a tragedy to put prudent security measures in place at borders and boarding gates.”
The database is available to law enforcement authorities but not to airlines.
Last year, passengers boarded planes more than a billion times without their passports being checked against Interpol’s database of 40 million stolen or lost travel documents.
The Civil Aviation Authority of Vietnam said a Vietnamese navy plane had spotted an object in the sea which was through to be part of the plane but it was too dark to find out for certain.
Search planes are due to investigate the suspected debris at daybreak.
It was found about 56 miles south of Tho Chu island, in the same area where oil slicks were spotted on Saturday.
A source involved in the investigations said: “The fact we are unable to find any debris so far appears to indicate the aircraft is likely to have disintegrated at around 35,000ft.”
They said if the plane had plunged intact from close to its cruising altitude, breaking up only on impact with the water, search teams would have expected to find a fairly concentrated pattern of debris.
They added that there was no evidence yet of foul play, and the aircraft could have broken up due to mechanical causes.
Dozens of military and other vessels have been criss-crossing waters beneath the aircraft’s flight path, but have found no confirmed trace of the lost plane.
Malaysia’s air force chief said the plane may have turned back from its scheduled route before it vanished from radar screens.
Rodzali Daud said: “What we have done is actually look into the recording on the radar that we have and we realised there is a possibility the aircraft did make a turnback.”
That could suggest the pilots were forced to change course.
Malaysia Airlines chief executive Ahmad Jauhari Yahya said pilots were supposed to inform the airline and traffic control authorities if the plane does a U-turn.
He said: “From what we have, there was no such distress signal or distress call per se, so we are equally puzzled.”
Establishing what happened with any certainty could need data from flight recorders and a detailed examination of any debris.
Malaysia Airlines told relatives they should “prepare themselves for the worst”.
Meanwhile, the UK offered assistance with investigations.
Foreign Secretary William Hague said it was “too early to speculate” on the significance of the presence on the flight of passengers with suspect identities.
He added: “It is a terrible tragedy and our thoughts are with the families and loved ones of people awaiting for definitive news. We have offered any assistance that we can give to the Malaysian authorities and we have been checking up on whether any British nationals were involved. We are not aware of any at the moment.”
Asked about the significance of the suspect identities, he said: “It is too early to speculate about what that means.
“The UK will assist the Malaysian authorities in any way we can with any investigation if it is relevant to do so in any way.”
Malaysia Airlines has a good safety record, as does the 777, which had not had a fatal crash in its 19-year history until an Asiana Airlines plane crashed last July in San Francisco.
Passengers aged 2 to 76 had different stories to tell
Numbered up to 227, the passenger list for the missing Malaysia Airlines jet is an outwardly unremarkable document.
Behind the columns of names, nationalities and ages are 227 stories, a rich human tapestry gathered to take a flight. There were middle-aged Australians with wanderlust, an acclaimed Chinese calligrapher, a young Indonesian man heading to begin a new career, and two people travelling on stolen passports.
Since the Boeing 777 disappeared from radar screens in the first hour of a six-hour flight from Kuala Lumpur, Malaysia, to Beijing, families and friends from France to Australia and China have been enduring an agonising wait for news.
The flight had a crew of 12, all from Malaysia, including ethnic Malays, Chinese and Indians. Passengers on the popular business and tourist route were mostly from China and Malaysia, along with a smattering of people from other corners of the world: Americans, Australians, Indians, French, Indonesians, Ukrainians and other nationalities.
Some travelled alone, some were in groups. Passengers included young sweethearts and older couples. A 74-year gap separated the youngest, two-year-old Moheng Wang, and the oldest, 76-year-old Rusheng Liu.
“I can only pray for a miracle,” said Daniel Liau, the organiser of a calligraphic and painting exhibition in Malaysia attended by acclaimed Chinese calligrapher Meng Gaosheng, who boarded the flight with 18 other artists plus six family members and four staff.
“I feel very sad. Even though I knew them for a short time, they have become my friends,” Mr Liau said.
Also travelling as a group were eight Chinese and 12 Malaysian employees of Austin, Texas, semiconductor company Freescale, which said it was assembling “around-the-clock support” for their families.
Each day more than 80,000 flights take off and land around the world without incident. For seasoned Australian travellers Robert Lawton, 58, and his wife, Catherine, 54, the seemingly routine take-off of flight MH370 was the beginning of another adventure.
“They mentioned in passing they were going on another big trip and they were really excited,” said Caroline Daintith, a neighbour who described the couple as doting grandparents.
Sharing their adventure was another 50-something Australian couple, Rodney and Mary Burrows.
Niluksi Koswanage: Missing pilot ‘was an aviation tech geek who you could ask anything’
The pilot of the Malaysia Airlines jet that went missing on Saturday enjoyed flying the Boeing 777 so much that he spent his days off tinkering with a flight simulator of the plane at home, fellow workers said.
Zaharie Ahmad Shah, 53, captain of Flight MH370, which was carrying 239 people bound for Beijing from the Malaysian capital Kuala Lumpur, had always wanted to become a pilot and joined the national carrier in 1981. Airline staff said Mr Shah knew the ins and outs of the Boeing 777 extremely well, as he was always practising with the simulator. They declined to be identified due to company policy.
“He was an aviation tech geek. You could ask him anything and he would help you. That is the kind of guy he is,” said a Malaysia Airlines co-pilot who had flown with Mr Shah.
Mr Shah set up the Boeing 777 simulator at his home in a suburb on the outskirts of the Malaysian capital where many airline staff live as it provides quick access to the Kuala Lumpur International Airport.
Pictures posted by Mr Shah on his Facebook page show a simulator with three computer monitors, a tangle of wires and several panels.
“We used to tease him. We would ask him, why are you bringing your work home,” said a pilot who has known him for 20 years.
Mr Shah’s passion for aviation went beyond the Boeing 777. Other photos posted by him on Facebook show he was an avid collector of remote-controlled, miniature aircraft, including a lightweight twin-engined helicopter.
Mr Shah was certified by Malaysia’s Department of Civil Aviation (DCA) as an examiner to conduct simulator tests for pilots, said officials from Malaysia Airlines.
They said it was impossible that he would be in any way to blame for the disappearance of the aircraft.