(CNN) -- One of the few mysteries to have light shed on it in the search for a missing Malaysia Airlines airliner has been the case of two passengers who boarded the flight with stolen passports. The news that two Flight 370 passengers were not who they claimed to be -- and had used stolen documents -- immediately raised speculation about foul play. Authorities have not ruled out terrorism, but at least where it concerns these two passengers, early evidence indicates they were, foremost, Iranian migrants. Interpol Secretary General Ronald Noble identified the two as Pouri Nourmohammadi, 18, and Delavar Syed Mohammad Reza, 29. He said they entered Malaysia using valid Iranian passports, but they used stolen Austrian and Italian passports to board Flight 370.
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Malaysia is a favored destination for people fleeing Iran
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It is a destination that does not require visas for most Middle Easterners
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Human Rights Watch official: It is relatively easy to get a stolen passport
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The passports were stolen in Thailand, a hub for high-quality fake documents
After the violent 2009-2010 election protests in Iran, many @placeholder fled for Malaysia, where Middle Easterners, in most cases, can travel without a visa, Robertson said.