The U rated flick first aired in 1970, and stars Jenny Agutter and Bernard Cribbins. It tells the story of three children who move from London to Yorkshire with their mum after their father is wrongly imprisoned.
The children are seen on the railway line in various scenes in the film, most memorably as they flag down a train to warn its driver of a landslide.
The Sun reports that British Board of Film Classification responded to the complaint by saying that although the movie 'clearly illustrates the dangers of going on to the tracks' it was acceptable because it was 'set in a very different era'.
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