Italian tourists watching the view from a fairground Ferris wheel at Munich Oktoberfest go through embarrassing moments on Friday when a porn shoot suddenly starts inside their cabin.

Two men suddenly appeared with cameras, while a woman started using vibrator.

Local police arrested the actress and her crew, a political scientist and a 25-year-old student.

"They said they weren't doing it for commercial reasons but that they wanted to see how visitors would react," police say. The three have been charged with public indecency.