One of the elves was so disturbed by the nightmare before Christmas that they resigned on the spot.

Grotto organiser Penny Ward was astounded when nearly 2000 families arrived with vouchers from Groupon, which had mistakenly sent an email to customers saying that there would be a train ride around the winter wonderland.

When people discovered no train ride was in action thy began swearing at staff, who were dressed as elves, fairies and a Christmas tree.

One man even threatened a lady who dressed as a Christmas tree.

“One of the elves was so upset that she has resigned,” Ward said. “It was a complete nightmare. Children were crying and upset.”

Ward said the parents were mostly from from Newcastle and had come down to St Nicholas Fayre, a popular Christmas market in York.

She said the grotto was only able to handle 40 children an hour, but dedicated staff had worked beyond their normal hours and without breaks to try and make sure no one missed out.

Ward used Groupon’s services to publicise the grotto but was adamant that she never promised a train ride.

She thought the York grotto may have been mixed up with a grotto she ran in Hull, where there was a train ride.

A Groupon spokesman said: “Owing to a technical error, we apologise that the picture and wording used in this promotion may have indicated that a train ride was available at York Winter Wonderland when this wasn’t the case. We regret any disappointment this may have caused.

“We hope that this hasn’t taken away from the Santa’s grotto experience and we wish everyone a happy holiday season.”

But here at TNT all we’re worried about is whether the poor little elf is OK.