A British tourist took a video on his mobile phone during the terrifying moment his plane got into trouble and made an emergency landing.
Ethan Williams, 25, was flying from Hong Kong to Los Angeles with Cathay Pacific when smoke was detected on board.
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He is heard saying: "I'm not sure what's happening but there's something happening on this flight.
"All the flight attendants are running around like crazy and warning signs going off, hopefully it's not anything too bad and we'll be alright."
He then adds: "We've just had an announcement, we've got an emergency landing. We've not been told what is going on but we've got an emergency landing."
Williams then puts on a life jacket and a crew member tells passengers what to do when they hear the word 'brace'.
The Express reports that the jet landed safely at Eareckson Air Station, a US air base in Shemya, Alaska. Relieved passengers broke into a round of applause and Ethan said: "We've landed – yes! Still don't know why, but we're down."
According to the Mirror, the airline tweeted that a "preliminary inspection indicates that an equipment cooling fan below the cabin floor near the cargo compartment had failed."
"Safety will always remain our top priority and we will conduct a thorough investigation into the cause of this incident."
Mr Williams tweeted a copy of a letter that passengers were given telling them they would receive a cash card worth $300 as "a token of our thanks for your patience and understanding".
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