UPDATE: Pouria Nour Mohammad Mehrdad and Delvar Suyed Mohammad Reza have been named by Interpol as the two Iranians who used stolen passports on board the Malaysian Airlines flight which disappeared over the South China sea.
Officials have identified a 19-year-old Iranian passenger travelling on stolen passport on the doomed Malaysian Airlines flight headed for Beijing, and have said he was probably trying to emigrate to Germany.
The Iranian man had no known links to terror groups, police chief Tan Sri Khalid Tan Sri told a press conference in Kuala Lumpur on Tuesday morning, holding up an image of the man on a piece of paper.
The second passenger using a stolen passport has not been identified.
Hijacking, or a psychological breakdown by a member of the crew or pilot, has not been ruled out. "Other than mechanical problems, these are the main areas of concern," said Malaysia's inspector general, Tan Sri Khalid Abu Bakar
He also dismissed earlier reports that five passengers had checked in to flight MH370 over the weekend and not boarded the plane, saying such reports were untrue.
China has reassigned 10 of its satellites to speed up locating the missing plane, which disappeared over the South China sea. No debris, or indeed any trace of the plane has been found in the days following its disappearance, leaving searchers baffled.
The search is now being concreted on the Malaysian coastline, looking at a possibility of an attempt made by MH370 to turn back to Subang. Around 40 ships and 34 aircraft are taking part in the search.
In a statement, Malaysia Airlines said: "The search and rescue teams have expanded the scope beyond the flight path."
"All angles are being looked at. We are not ruling out any possibilities.
"Apart from the search in the sea, search on land in between these areas is also conducted."
On Monday, the country's civil aviation chief told a news conference two passengers who boarded missing Malaysia Airlines flights MH370 were not "Asian-looking" but resembled footballer Mario Balotelli.
The US says it has reviewed imagery from satellites for any indication of a mid-air explosion, with no success.
Sightings of debris from a Vietnamese plane has now been discounted as evidence of a crash, as has an oil slick, which tests have shown was a type used by ships in the cargo-heavy sea.