Passengers have described their terror when a Singapore Airlines flight from London to Singapore dropped suddenly.  

A 73-year-old British man has died of a suspected heart attack and dozens of others were injured.  

A statement from the airline says 23 of the 211 passengers were from New Zealand.  

Flight SQ321 was diverted to Bangkok.  

UK correspondent Gavin Grey told Mike Hosking that the plane fell seven thousand feet in six minutes, causing mid-air chaos. 

Seven other passengers are critically injured with head injuries. 

Singapore Airlines says 18 people have been hospitalised in Bangkok. 

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