ROME (Reuters) - International police agency Interpol said at least two passports recorded as lost or stolen in its database were used by passengers on board a missing Malaysia Airlines flight, and said it was "examining additional suspect passports" on Sunday.

Interpol said no checks of its database had been made by any country on an Austrian and an Italian passport between the time that they were stolen and the departure of the flight.

"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," Interpol Secretary General Ronald Noble said in a statement.