EasyJet has apologised for “any inconvenience” and launched an investigation. Casper was preparing to take only his second flight alone to stay with family in France, his mother Stephanie Portal told The Guardian.“It’s crazy,” she said. “They left him alone in departures. Luckily, I had still not got on board my train to London and could come back and find him. “If I had not been there I don’t know what would have happened – he’d have had no money for the train back or anything.” Ms Portal said she persuaded EasyJet to allocate her son a seat on the final flight of the day to Toulouse. The teenager was taken from his seat before the flight could leave Gatwick AirportCredit:Oli Scarff/Getty In April, United Airlines found itself at the centre of a furore after a passenger was forcibly removed from a flight.David Dao, a doctor, suffered concussion and a broken nose when he was dragged down the plane after he refused to leave his seat. An EasyJet spokeswoman apologised “for any inconvenience caused” by the incident.She added: “EasyJet is sorry that Casper Read’s flight from London Gatwick to Toulouse was overbooked. We are investigating why he was able to board the aircraft as he should have been informed at the gate.“EasyJet has a procedure to protect unaccompanied minors but unfortunately this was not followed on this occasion and so this will also be investigated.” Want the best of The Telegraph direct to your email and WhatsApp? Sign up to our free twice-daily Front Page newsletter and new audio briefings. An unaccompanied child was left alone at an airport departure gate after being removed from an overbooked EasyJet plane.Casper Read, 15, was taken from his seat before the flight to Toulouse could leave Gatwick Airport.The schoolboy, from Worthing, West Sussex, had been given a boarding pass for a seat on flight EZY833 on Thursday morning.But, having texted his mother to tell her he was safely on board, another passenger reportedly claimed Casper’s seat and he was told to leave the plane as there was not enough space.