The first round of Harry Potter and the Cursed Child tickets for June to September 2016 have sold out in hours.

And not long after booking opened at 11am, tickets started popping up on resale websites, with some priced at more than £3,000.

But according to the terms and conditions, these tickets may be void.

“We reserve the right to refuse admission to customers with tickets purchased on re-sale websites,” the Cursed Child website says.

“Tickets purchased through either of our official ticketing platforms must not be sold or advertised for sale on the internet, in newspapers or elsewhere.”

Because of the high demand, producers also released the next batch of tickets, for dates up to January 2017, to people who have got priority booking.

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Public booking doesn’t even open until Friday 30 October, so you may think that it’s worth taking your luck with the re-sellers but the production website warns: “Any ticket advertised for sale in this way will be automatically void.

“Please note, the credit and debit card that you used to purchase your ticket, or confirmation email will be required as proof of purchase when you get to the theatre.”

Newsbeat has contacted Viagogo, StubHub and GetMeIn, resale sites which all have Harry Potter and the Cursed Child tickets listed. GetMeIn has yet to make a comment.

“It is perfectly legal to resell tickets,” a spokesperson for Viagogo tells Newsbeat.

Their statement adds: “Incidents of people having a problem with their ticket are extremely rare.

“However, if a problem arises, we will either step in and provide replacement tickets, or a full refund in the extremely rare instance where that is not possible.”

A StubHub spokesperson said: “Tickets listed at very high prices rarely sell on our site. As a true marketplace, StubHub does not own, price or purchase any tickets listed on the site.

“The price that you see is set by the seller and what they think the market will bear. Sometimes for events or performances with higher demand, sellers will list prices that are higher than the original primary face value.

“Similar to eBay, our parent company, StubHub does not restrict how high or low a seller wishes to list a price.”

If you genuinely cannot use the tickets you have bought, then more details about refunds will be made available in December.

The prices for a ticket range from £10 at the previews, to £65 for the most expensive seat.

Because the play is in two showings, customers who want to get the full story need to but a ticket for part one and another for part two.

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Fans were given a sneak peek at the production last week, when producers revealed details of the plot and some artwork.

The Cursed Child is going to be a sequel to Rowling’s books, focusing on Harry’s son Albus Severus.

“While Harry grapples with a past that refuses to stay where it belongs, his youngest son Albus must struggle with the weight of a family legacy he never wanted,” a synopsis reads.

“As past and present fuse ominously, both father and son learn the uncomfortable truth: sometimes, darkness comes from unexpected places.”

The production takes place at the Palace Theatre in London.

Pictures of artwork with the tagline, “The eighth story. Nineteen years later,” have also appeared online.

Harry Potter fans have suggested the nest and wings in the picture are reminiscent of a Golden Snitch, the smallest ball used in a game of Quidditch.

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