"Sidmouth invaded by ___ "

At 26 minutes into 'Have I Got News For You' on BBC One last Saturday evening, you might have been taken aback by this headline:

BBC iPlayer - Have I Got News for You: Series 47: Episode 3

The various answers proposed by the panel were:
> 'Russia'
> 'Flying Insects'
> 'Moths, seals, Methodists'

But the right answer was, of course:
> 'onions'

‘Sidmouth being invaded by onions!’ - News - Sidmouth Herald
Beautiful blossoms of Sidmouth are being undone by smelly, wild invader | Western Morning News

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