British Airways Cabin Fills with Smoke, Prompting Evacuation: 'Felt Like Horror Film'

British Airways flight BA422 from London to Spain was forced to evacuate after smoke filled the plane cabin.

As the aircraft was landing in the Valencia Airport during the final leg of its flight, it began to experience technical issues that eventually filled the entire cabin and pilot cockpit with smoke, according to a BA spokesman.

“Flight BA422 from Heathrow to Valencia experienced a technical issue on its landing approach into Valencia. All our customers were evacuated safely by our crew and met by the airport’s emergency services,” the spokesman told PEOPLE in a statement.

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There were 175 passengers, in addition to two pilots and six cabin crew members on board.

“Three customers were taken to the hospital as a precaution and have since been discharged,” the airline confirmed to PEOPLE.

A passenger aboard the flight shared the experience on Twitter, describing it as a “horror film.”

“.@British_Airways terrifying experience on flight to Valencia. Felt like horror film,” Lucy Brown tweeted following the incident. “Thankfully everyone safe. Flight filled with smoke and had to be emergency evacuated.”

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Brown later spoke to CNN about the harrowing experience, recalling the emergency evacuation and how the oxygen masks did not release.

“We covered our mouths with our clothes. We don’t know why oxygen masks didn’t deploy,” she said, revealing that the smoke was thick and smelled of chemicals. “Passengers started shouting they couldn’t breathe.”

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She added that it took nearly 15 minutes for the emergency doors to open.

The British Airline Pilots’ Association explained why oxygen masks “did not deploy” in a statement on their website.

“Media reports include reference to the fact that passenger oxygen masks did not deploy. This is because they, unlike pilot and cabin crew oxygen systems, are not designed to be used in smoke events as they mix the oxygen supply with the ambient air,” the statement read. “Passenger oxygen masks are for use during decompression events.”

The BA spokesperson later added, “The safety of our customers and crew is always our highest priority. In addition to our team on-site, other British Airways team members have arrived in Valencia to help our customers and our local airport partners with anything they need.”