The company behind Alton Towers and Legoland has admitted tourists are shying away from its theme parks after a series of terror attacks around the UK.
In a trading update this morning, Merlin Entertainments, which also operates Madame Tussauds and the London Dungeons, said: "A number of our UK parks have been adversely affected in recent weeks by the terror attacks and subsequent heightened security measures."
Shares in the company slid 2.7 per cent to 489.05p in the first minutes of trading.
The company said trading in the first part of the year had benefited from strong UK tourism figures, pushed up by sterling's bargain basement valuation.
"This continued in the immediate aftermath of the Westminster attack on 22 March, although the incident did result in a softer domestic, day-trip market," it added.
"However, the subsequent attacks in Manchester and London over the past month have resulted in a further deterioration in domestic demand and, given the typical lag between holiday bookings and visitation, we are also cautious on trends in foreign visitation over the coming months."
There was some good news: its the company said it was making good progress on its plans to open more Legoland parks, with new openings in Melbourne, Philadelphia and Japan, as well as 250 hotel rooms in Florida and Billund, and a new Madame Tussauds in Nashville.
Chief executive Nick Varney chose to strike an optimistic note: "The impact of recent terror attacks on our London attractions is unclear at this stage. What is clear however is that London has bounced back before, and will do again," he said.
"I have every confidence in the longer term resilience and growth trajectory of the market. London is very much open for business, welcoming visitors from the UK and from around the world to this exciting and vibrant city.
"I remain confident in the company's underlying growth prospects."
Today's slide in shares comes just two months after Merlin said it was recovering "well" following a crash on the Smiler ride at Alton Towers in 2015, during which 16 people were injured, including two girls who needed leg amputations.