Two Muslim American YouTube stars who were returning home to New York after a world tour said they were removed from a Delta Air Lines flight in London on Wednesday after other passengers expressed discomfort with their presence on the plane.

Adam Saleh, 23, a filmmaker from Manhattan, and his friend Slim Albaher, 22, from Bay Ridge, Brooklyn, said they had been asked by the captain to leave their flight at Heathrow Airport after Mr. Saleh spoke in Arabic to his mother by phone, and he and Mr. Albaher followed up by speaking to each other in Arabic, causing alarm among British passengers on the flight.

The news was met on social media with anger at the airline industry, but also skepticism, though passengers who were on the plane when it landed in New York corroborated the men’s story. Mr. Saleh, who has more than two million subscribers on YouTube, has a history of perpetuating video hoaxes and pranks, some of them aimed at exposing stereotypes about Muslims. In his latest YouTube video, posted this month, he pretended to smuggle himself onto a plane in a suitcase.

In a phone interview Wednesday from Heathrow before he and Mr. Albaher boarded a later flight, Mr. Saleh said this was not a stunt. “The only thing I can say is, I would never film a phone video,” he said. “That’s when it’s really serious, and I must film.” His video camera was in his luggage.