Paul Shane, who has died aged 72, played butler Alf Stokes in the sitcom You Rang M'Lord?, which aired from 1990 to 1993.
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In an email to the actor, Twitter said the tweet “has the potential to be misleading in a way that could impact an election”.
The man was detained by security staff on Sunday evening.
The Duke of Sussex will make a speech at the Loughborough University event.