Legoland in Windsor has cancelled the Muslim Research and Development Foundation (MRDF) family fun day due to take place on Sunday, March 9
The decision came after discussions with police following a number of threatening phone calls, emails and social media posts to the resort, which is in Winkfield Road.
Groups including the EDL planned to demonstrate on the day.
The MRDF is led by Haitham al-Haddad, who was identified by the government last year as being one of Britain's top 25 hate preachers.
Legoland's statement on their website says: "The Legoland Windsor Resort prides itself on welcoming everyone to our wonderful attraction; however due to unfortunate circumstances the private event scheduled for Sunday 9th March will no longer take place.
"This was an incredibly difficult decision made after discussions with the organisers and local Thames Valley Police, following the receipt of a number of threatening phone calls, emails and social media posts to the Resort over the last couple of weeks.
"These alone have led us to conclude that we can no longer guarantee the happy fun family event which was envisaged, or the safety of our guests and employees on that day – which is always our number one priority.
"Sadly it is our belief that deliberate misinformation fuelled by a small group with a clear agenda was designed expressly to achieve this outcome.
"We are appalled at what has occurred, and at the fact hat the real losers in this are the many families and children who were looking forward to an enjoyable day out at Legoland. We would like to apologise to them and to the organisers, and to thank them for their understanding. We hope that they will all be able to come to visit us during the season."
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