Concertgoers were turned away from a Mumford & Sons gig in Portsmouth after being found to have fake tickets.
Police received a report that about 100 people were refused entry to the city’s guildhall on Thursday night.
Fan Paula Wynne told BBC News her partner had bought a pair from resale website Viagogo for £200.
Viagogo said duped fans would be offered real tickets to a future Mumford & Sons gig or a voucher to the value of the original purchased ones.
[contentblock id=34 img=gcb.png]
Portsmouth Guildhall said it was working with police to investigate.
A statement on the band’s website said: “We sincerely hope that not too many of you good honest Mumford & Sons fans have been affected.
“If you have purchased tickets from any secondary vendors then we would urge you to seek your money back immediately.
“Remember to always purchase tickets from official vendors only.”