The aircraft, which was traveling to Edinburgh, Scotland, took off from Budapest, Hungary, on Jan. 31, according to reports. About an hour into the flight, however, the first of the four passengers — a 17-year-old — allegedly fainted, passengers say.
Another passenger soon fainted, followed a third, and then another passenger after.
Ryanair crew members reportedly administered CPR and oxygen.
A representative for Ryanair added that the crew also called ahead to the Edinburgh Airport to request medical assistance upon landing.
The Edinburgh Airport confirmed that medical personnel met with the flight when it arrived, according to The Independent.