An easyJet flight from Manchester Airport was forced to make a mid-air U-turn due to "extraordinary circumstances".
The plane, which was bound for Alicante, took off at 6pm, but landed again just 30 minutes later.
The flight turned around over the English Channel and landed at London Gatwick.
A second flight was then scheduled to take those onboard from Gatwick to Alicante at 9pm on Wednesday.
The easyJet flight was forced to make a U-turn due to 'extraordinary circumstances'
|PA
Customers onboard were reportedly told that the flight was forced to make the U-turn due to "extraordinary circumstance".
EasyJet has since confirmed that a customer onboard the flight required urgent medical attention.
An easyJet spokeswoman said: "Flight EZY2033 from Manchester to Alicante on 27 August diverted to Gatwick due to a customer requiring urgent medical attention.
"The customer was met by medical services and the flight then continued to Alicante.
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The flight took off from Manchester Airport at 6pm
| GETTY"The safety and wellbeing of our customers and crew is always easyJet’s highest priority."
According to its website, in the case of a diversion, the airline vows to "do all that we can to get you to your final destination".
The UK Civil Aviation Authority (CAA) explained that if the diversion is due to a "disruptive passenger" then it may be asked to reimburse the airline with the cost of the diversion.
It added: "Diversion costs typically range from £10,000 to £80,000 depending on the size of the aircraft and where it diverts to."
The flight landed just 30 minutes later at London Gatwick
| PAAccording to the CAA, disruptive passenger behaviour is one of the main reasons an aircraft is diverted.
Other than disruptive behaviour, diversions can also be due to health issues which require urgent medical attention.
If this is the case, pilots will divert to the nearest suitable airport for treatment.