Some printed Elton John tickets will no longer be valid after a last-minute change – sparking warnings of "pandemonium" ahead of this weekend's concerts.

Ticketmaster customers who printed their tickets early will have to reprint them because of new "additional entrance information", or risk being denied entry.

In an email to customers headed ‘*Important Information* Elton John - Vicarage Road Stadium, Watford’, Ticketmaster said: "We've added some additional entrance information to your tickets so any that you've already printed will no longer be valid to gain entry.

"To make sure you won't have any problems getting into the event on the day, we've made some adjustments to your tickets, and you'll need to reprint them from your online account."

However, Ticketmaster added that mobile tickets can also be accepted.

The company added: "Don't worry if you don't have access to a printer, you can show the ticket/barcode on your phone upon entry.

"We're sorry for any inconvenience caused."

Watford Observer: The email sent to customers going to the Elton John concerts in WatfordThe email sent to customers going to the Elton John concerts in Watford

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Some customers were enraged.

Elton fan Peter Morgan said: “It is absolutely disgusting.

“I spent ages the last two days printing 26 tickets for myself, friends and family for the Elton John concert, to be told this.

“Between us we paid hundreds of pounds in spurious service charges and the like for the tickets – £10 plus per ticket.

“How many people will have printed tickets and not see the message and so cannot get in on the night.

“It is a recipe for complete pandemonium.”

Former Watford FC chairman and lifelong Hornets fan Sir Elton will be performing at Vicarage Road on Sunday and Monday.

Ticketmaster has been approached by the Watford Observer.

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