No one knows where this Boeing 737 that was stolen from an airport in 2003 ended up

Neither the FBI or CIA could get to the bottom of this one.

The Malaysian Airlines MH370 disappearance of 2014 has remained unsolved to this day, and a Netflix series that looked into how a plane carrying 239 passengers disappeared without a trace.

An unsolved case that goes much further back than that, is the case of the stolen plane from an Angolan airport in 2003.

On the 25th May 2003, two men boarded a parked up Boeing 727 at Aeroporto Quatro de Fevereiro in Luanda, and flew southwest over the Atlantic Ocean.

At the time, commercial aircraft weren't equipped with the same tracking technology as they are nowadays.

Not to mention the fact that this incident occurred just two years after 9/11, so everyone was on high alert.

Both thieves entered the cockpit, before switching off the lights and the transponder shortly after taking off from the airport.

One of the men was a US citizen and a private pilot, while the other was from Angola.

Since that day neither the men or the plane have been seen, and the mystery has not only baffled members of the public, investigators from both the CIA and FBI remained stumped as to what happened.

One of the main theories as to what happened involves legal troubles and dodgy dealings.

At the time that the plane was stolen, it was in the process of transferring the plane from one airline company to another.

There were reportedly a myriad of issues regarding the plane's lease and other financial hang-ups along the lines of payments missed and cased files.

As a result of all of this information coming to light, many speculated that both men who carried out the robbery were hired to do so in order to avoid legal troubles and commit fraud.

Over twenty years on and that's the explanation that is most often put forward, but nobody knows for sure.

While law agencies stepped back from the case in recent years because of lack of new information, it has never officially been closed and remains a mystery.

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