A holiday jet heading to Birmingham from Tenerife was forced to return to the Canary Islands' airport after a passenger set himself on fire with lighter fuel.
Horrified passengers had to endure a length delay on the tarmac whilst police were called to deal with the emergency which also saw the man attempt to burn an air stewardess's face.
Another passenger on board the Monarch flight said they had been unable to disembark for more than seven hours.
Monarch flight ZB933A left Tenerife South airport as planned on Thursday morning but turned round and headed back because of 'the disruptive behaviour' of two passengers. The incident was not terror-related.
One woman on board later said a passenger had set fire to his hands with lighter fuel.
She told ITV News: 'After taking off at 11.20am this morning, a passenger was setting fire to his own hands, so the stewardess asked the passenger for the lighter for the duration of the flight.
'He refused and attempted to light the lighter in her face. This information was forwarded to the pilot who decided to divert back to Tenerife South airport where the man was arrested.'
Fellow passenger Hannah Betteson tweeted: 'We was flying for an hour and had to turn back to Tenerife because somebody had lit a lighter [at] a stewardess.
She later added: 'Been flying since 10.30 this morning and I'm not even nearly home.'
The incident was also confirmed by another passenger who told friends on Tenerife that the man had threatened to set light to himself.
He said they had to stay on the aircraft until the Civil Guard arrived.
The man was reportedly arrested by Spanish police after the plane re-landed at the Tenerife airport. It is understood a second person was also ordered off the aircraft.
After some delay, the remaining passengers were later flown to Portugal where they faced further lengthy wait before getting back to the UK today.
A Monarch spokesman said: 'Monarch can confirm that two passengers were offloaded on board Monarch flight ZB933 from Tenerife to Birmingham on 27 October 2016 due to disruptive behaviour.
'The flight had departed for Birmingham but diverted back to Tenerife airport where a passenger was subsequently arrested upon arrival.'
The spokesman added: 'Due to crew operating hours expiring the flight is now positioning to Faro, Portugal where a new crew will be available for the return to Birmingham. Customers will be provided with refreshment vouchers upon arrival in Faro.
'Monarch takes a zero tolerance approach to disruptive behaviour on board all of our flights. The safety and security of our passengers, crew and aircraft is our absolute priority.'