Black Sabbath fans snapped up thousands of tickets for the band's appearance at Hyde Park next week for just £2.50 each.
A 'secret' link meant for employees of the event organisers was leaked, allowing regular punters to buy the heavily discounted briefs for Sabbath's British Summer Time show – as well as tickets for all the other BST gigs.
The full price tickets start at £69.
After the link had been doing the rounds online, there was confusion as some fans reported via social media that they have been told they will be refunded for their purchases, while others say they were told they can attend the shows.
However, BST Hyde Park's Facebook page posted this statement this afternoon: "Hi All, A staff ticket offer was leaked earlier today and some members of the general public were able to purchase reduced price tickets to certain Barclaycard presents British Summer Time Hyde Park concerts. That offer has now been stopped.
"If you were lucky enough to purchase a ticket from this offer rest assured that your ticket remains valid."
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