Emergency runway closure at Heathrow
Both runways were closed at Heathrow Airport after a British Airways plane made an emergency landing, the airport has said.
All passengers and crew were "safely evacuated" from the plane following the incident at about 09:00 BST.
John Coghlan told the BBC he saw a "black smoke trail" from the engine of a British Airways Airbus A319.
He said: "[It was a] safe landing and passengers evacuated by chutes on runway." There was "no fire", he added.
The southern runway has since re-opened. The northern runway remains closed.