
Turkish Airlines Flight 15 departed Istanbul en route for Sao Paulo, Brazil, until the note was found.
The plane, a Boeing 777, landed safely in Casablanca, Morocco, the airline said.
No explosives were found on the plane, the airline said.
The airline said this was the second time in two days that a flight was diverted because of a similar threat.
On Sunday, a Turkish Airlines flight that took off from Istanbul turned around and returned to the airport after a note that said "C-4 cargo" was found in a bathroom. C-4 is a common type of explosive.
No explosives were found on that flight, either, the airline said.
Comment: Between this and today's nationwide blackout in Turkey, is someone trying to send the Turkish government a message?
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