They definitely won’t forget this trip to Spain anytime soon. Passengers on board the flight BA422 from British Airways, left Heathrow airport in London and were calmly making their way towards the Iberian Peninsula when an incredible scene took place 10 minutes before they were supposed to land, leaving passengers to fear the worst.The cabin started filling with smokeThe white, hazy smoke started filling the cabin of the plane, causing the cabin crew and passengers to panic and forced the pilot to perform an emergency landing in the airport in Valencia in Spain, as The Huffington Post reported.The passengers were immediately evacuated and some of them shared photos and videos of their suffocating experience on social media.‘Terrifying experience on flight to Valencia. Felt like horror film. Thankfully everyone safe,’ wrote one passenger on Twitter.When questioned by the BBC, one passenger reported that the smoke started to fill the cabin ‘very quickly’ about ten minutes before it was scheduled to land in Valencia.‘You couldn’t see the passengers two seats down from you,’ she explained.The cause of this accident remains unknownFor now, what caused this incident is still unknown. The emergency services in Valencia apparently received an alert indicating that one of the plane’s motors had caught fire. As for British Airways, they simply called it a ‘technical issue’. In a tweet, one passenger said that the Spanish police thought there was a fire in the hold. Check out the video see exactly what happened!