Update | Terror probe launched into missing Malaysia Airlines jet as passenger list is scrutinised

A terror probe involving the FBI and counterterrorism units from around the world was launched on Sunday into the disappearance of a missing Malaysia Airlines jet, as officials said they were investigating four people on the Boeing 777 flight from Kuala Lumpur to Beijing.

More than 36 hours after the last contact with flight MH370, the entire passenger list was being scrutinised as Malaysian officials worked to verify the identities of all those on board.

Foreign ministries earlier revealed that at least two tickets on the flight had been booked with stolen passports.

The passenger manifest issued by the airline included the names of two Europeans - Austrian Christian Kozel and Italian Luigi Maraldi - who, according to their foreign ministries, were not on the plane. Both had apparently had their passports stolen in Thailand during the past two years.

The BBC reported that the men using their passports had purchased tickets together and were flying on to Europe from Beijing, meaning they did not have to apply for a Chinese visa and undergo further checks.

An employee at a travel agency in Pattaya, in Thailand, said the two had purchased the tickets there.