A Germanwings flight to Venice was diverted to Stuttgart on Saturday as the Airbus A319 aircraft appeared to be losing oil, the airline said in a statement.
Germanwings flight 4U814, with 123 passengers and five crew members on board, took off from Cologne at 9:55 am (local time ).
Germanwings said the pilots shut off one of the aircraft's engines and headed for Stuttgart when the problem was detected.
"This is a standard safety procedure. It was not an emergency landing," it said, adding the aircraft was being examined by technicians.
Germanwings, a budget unit of German airline Lufthansa has been in the spotlight after one of its planes crashed into a mountain in the French Alps last week, killing everyone on board.
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