American Airlines is investigating a mystery illness on a transatlantic airliner. At least six people became sick Wednesday on Flight 109 from London to Los Angeles.
Passengers say it began as a routine 10-hour flight, reports CBS News correspondent Kris Van Cleave. Then, about two and a half hours after takeoff, the crew turned on the cabin lights and asked if there was a doctor on board.
"It was probably as tense as anyone wants to be 30,000 feet in the air," passenger Eric Winter said.
He was one of the 172 passengers on the flight,
"I saw an older gentleman -- unfortunately, he had thrown up all over himself," Winter described.
British boy band Race the Horizon was also on board and said a flight attendant collapsed in the aisle.
"It was just a shock really. She was walking down the aisle, I don't know she just like sort of literally fainted in front of me," band member Kris Evans said.
The four-year-old Boeing 777 departed London's Heathrow Airport around noon on Wednesday for Los Angeles. Once in the air, the airline said two passengers and several flight attendants complained of lightheadedness. According to witnesses, two people fainted. Winter said a doctor and a medical student volunteered to help.
"They owned that cabin and made sure everyone was as safe or as comfortable as they needed to be," Winter said.
According to maps tracking the plane's flight path, the captain turned around just miles from Iceland's largest international airport.
"The pilot came on and spoke to everyone and said, 'Listen, the three of us are safe up front. We have zero problems, we're taking us back to London,'" Winter recalled.
Teams of first responders, including a hazmat unit, met the aircraft at the gate. London's ambulance service says it treated and released six patients at the scene who were not feeling well.
Winter commended the pilots and crew for their professionalism.
"In the absence of information, your mind can go crazy, but I think they did a tremendous job," he said. "They communicated to us every step of the way. And here we are. We're sitting on the ground and we're fine."
American says a hazmat team checked the plane and all of the luggage. Maintenance crews also inspected the entire aircraft. So far there's no sign anything was wrong, but the aircraft is being thoroughly cleaned.
The decision to return to London instead of diverting to Iceland would be up to the captain. Returning to London would make it easier to re-accommodate passengers.