Two airliners have been photographed appearing to fly in formation as they pass over Liverpool.
Images suggest the aircraft were side by side, although they do not show the difference in altitude.
Data published by flight tracking website Flightradar24 suggests there was 2,000ft of separation between the planes as they flew over Liverpool shortly before 1pm on Wednesday.
Two passenger aircraft appearing to fly in formation as they pass over Liverpool (Peter Byrne/PA)
The plane on the right of the photographs is believed to be Turkish Airlines flight TK12 from New York to Istanbul, flying at 35,000ft.
It was pictured next to a KLM cargo flight from Miami to Amsterdam, which was at 37,000ft.
Air traffic rules require aircraft to maintain a vertical separation of at least 1,000ft.