LONDON (AP) — The U.K.'s competition watchdog has launched an investigation into the way tickets were sold for next year's reunion concerts from iconic 1990s Britpop band Oasis.

In a statement Thursday, the Competition and Markets Authority (CMA) said its investigation into Live Nation Entertainment's unit Ticketmaster will look specifically at “dynamic pricing," whereby prices can vary rapidly in light of changing market conditions.

Many Oasis fans who queued online at the Ticketmaster site for many hours on Saturday complained that they ended up paying more than double the face value of the ticket as a result of this dynamic pricing.

The watchdog said it would scrutinize whether the sale of Oasis tickets by Ticketmaster may have breached consumer protection law and whether the company engaged in unfair commercial practices.

“It’s important that fans are treated fairly when they buy tickets, which is why we’ve launched this investigation,” said Sarah Cardell, the watchdog's chief executive. “It’s clear that many people felt they had a bad experience and were surprised by the price of their tickets at check-out.”

The band is led by brothers Noel and Liam Gallagher, who said in a statement Wednesday that they knew nothing about “dynamic pricing,” that they leave matters around ticketing to their management team.

The tickets that went on sale Saturday were for the band's concerts July 4 and 5 at Cardiff’s Principality Stadium, Heaton Park in Manchester, on July 11, 12, 16, 19 and 20, London’s Wembley Stadium on July 25, 26 and 30 and Aug. 2 and 3, Murrayfield Stadium in Edinburgh on Aug. 8, 9 and 12; and Croke Park in Dublin on Aug. 16 and 17.

On Wednesday, another two dates were announced at Wembley on Sept. 27 and 28. These will open only to people who were unable to get tickets in the initial Ticketmaster sale.

Formed in Manchester in 1991, Oasis was one of the dominant British acts of the 1990s, producing hits including “Wonderwall," “Champagne Supernova” and “Don’t Look Back in Anger.” Its sound was fueled by singalong rock choruses and the combustible chemistry between guitarist-songwriter Noel Gallagher and singer sibling Liam.

Oasis split in 2009, with Noel Gallagher quitting the band after a backstage dustup with his brother at a festival near Paris. While the Gallagher brothers, now aged 57 and 51, haven’t performed together since, both regularly perform Oasis songs at their solo gigs. They’ve also fired off criticisms of each other in the press.