BBC Springwatch presenter Chris Packham has been banned from the Game Fair taking place at Hatfield House.
Mr Packham was stopped, alongside conservationist Mark Avery and animal rights activist Jay Tiernan, from appearing at the Game Fair Theatre at Hatfield House today.
He blames lobbying from the British Association for Shooting and Conservation (BASC), Countryside Alliance and the Game and Wildlife Conservation Trust for the ban.
"I think it's because they are terrified," he said, because they keep "getting found out" about how they are treating game birds.
The BASC - a sponsor of the fair - said in a statement: "It is right that The Game Fair does not give a platform for an extremist like Chris Packham to air his anti-shooting views.
"The Game Fair is about celebrating the people who live and work in the countryside and continued polarisation of the debate by Mr Packham and others is of no benefit in this or any other medium."
The Welwyn Hatfield Times is yet to recieve a response from the Game Fair organisation team.
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