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Elton John is suffering from a serious respiratory infection and has been forced to cancel performances of his Las Vegas show "The Million Dollar Piano" on Thursday, Saturday and Sunday nights.

The singer first became ill last weekend but his condition worsened and he was hospitalized at L.A.'s Cedars-Sinai Medical Center on Wednesday. After undergoing tests for a day, a doctor recommended that Elton not perform for a week and follow a regimen of antibiotics and complete rest.

In a statement, John said, "It feels strange not to be able to perform these 'Million Dollar Piano' concerts at The Colosseum. I love performing this show and I will be thrilled when we return to The Colosseum in October to complete the eleven concerts soon to be scheduled."

He added, "All I can say to the fans is sorry I can't be with you. I hope to see you soon at this wonderful theatre at Caesars Palace."

Ticket holders can exchange their tickets or receive refunds.