A United Airlines flight bound for Los Angeles declared a "midair emergency" and made an emergency landing at London's Heathrow Airport on Friday after "sparks" were noticed in the first class cabin.
Flight UA935 landed at Heathrow Airport at 12:33 p.m. local time (7:33 a.m. ET).
"The captain announced that there were some sparks coming from two of the first-class seats," Ralph McLaughlin, who was aboard the Boeing 777 when it turned back while flying over Scotland, told NBC News. "I didn't see it because I'm in economy, but now the plane has landed I can smell some electrical smoke."
United spokesman Kevin Johnston said the plane returned "shortly after take-off because of a mechanical issue."
