Mercedes thwarted a Ferrari 'spy' during the post-race Abu Dhabi test on Wednesday.
Italy's La Gazzetta dello Sport and the German newspaper Bild published photographs of the blonde female Ferrari employee using an infrared video camera.
Wearing Ferrari team gear, she was using the camera in the spectator area immediately above the Mercedes team garage.
The reports said a member of the championship-winning Mercedes team went into the spectator area to ask his Ferrari counterpart to stop filming.
Asked what mission the 'spy' had been on, Ferrari told Bild: "Nothing special."