Seventh paragraph down ... Interpol Secretary General Ronald Noble said the two men had travelled from Qatar's capital Doha on their Iranian passports, and switched to stolen Italian and Austrian passports to board the Malaysia Airlines flight.
Good thought by you, TomGuy. Switched/Traded. If switched/traded whom has the switched/traded passports?
The passports were probably taken by “Mr. Ali,” the guy who arranged their flights and no doubt provided the stolen passports for them. Personally, I don’t think they were terrorists; just people attempting to sneak into a European country (where at least one of them, the one bound for Frankfurt, already had family).