ISTANBUL - A Turkish Airlines flight to Lisbon was diverted back to Istanbul on Wednesday but the reason was unclear, a spokeswoman told Reuters.
It was the third time in a week a Turkish Airlines flight was forced to change course. A Sao Paulo-bound flight landed in Morocco after a note with the word "bomb" was found in the lavatory on Monday.
On Sunday, a flight from Istanbul to Tokyo turned back shortly after take-off when another note was found on the lavatory door. Turkish Airlines is Europe's fourth-biggest carrier.