Three days after it went missing on its way to Beijing, there is still no sign of Malaysia Airlines Flight MH370, or any answer about what might have brought it down. The missing Boeing 777-200 had 239 people on board from over a dozen different nationalities. And even the identities of some of those passengers is a mystery: at least two people on board were traveling with what turned out to be stolen passports, leading to many rumors — some very sketchy — of a terrorist connection.

According to a report from the Financial Times, two unidentified men using those passports were booked on the flight through an Iranian contact. The passengers have since been isolated on video surveillance footage and the airport claims to have fingerprints, though no identities have been revealed.

According to FT, the men used stolen or lost Italian and Austrian passports. After landing in Beijing, the pair were supposed to fly to Amsterdam, and then split up: one was bound for Copenhagen, and the other for Frankfurt. Since the identities of the two men aren't yet known, there's no word on why they were using stolen passports: It could be anything from immigration to drug smuggling, or a wide range of other illegal activity.

Obviously, many have speculated that the stolen passports could be connected to terrorist activity, but there's no specific evidence to suggest that. Reuters reported on Monday that officials at the flight's departure airport in Kuala Lumpur have stopped "men with false or stolen passports and carrying explosives" on multiple occasions as they tried to board flights. 

Meanwhile, the relatives of the 239 people on board the jet are still waiting for answers, of which there have been few. The most promising lead as to the plane's fate — oil streaks in the water near where the plane vanished — turned out to be unrelated to the Malaysia Airlines plane. Reports of plane debris in the water were also deemed false. So now, ships and planes from 10 countries are widening their search for the aircraft in the hopes of discovering some clue about its fate. 

MH370 disappeared early Saturday local time, somewhere between Kuala Lumpur and Beijing. The pilot gave no distress signal before the plane went missing from radar, somewhere over the sea between Malaysian and Vietnamese waters.