Great Central Railway has issued a statement after a 'number of recent examples' of people on the line.
The incidents occurred on the route between Loughborough and Birstall, with staff having to confront joggers and walkers who had entered parts of the route not open to the public.
High speed trains are permitted along the line, which has remained in operation throughout the pandemic.
Great Central Railway said the trespassers appeared not to understand how, 'incredibly dangerous' it was for them to be there.
They added, "It is also against the law to access the premises for recreation, apart from public crossings, and all such transgressions will be considered trespass."
                                            
                                                    
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