Fans of heavy metal band Metallica were left furious after concert organisers delayed refunding money for a string of cancelled shows.

The band had been set to head Down Under this month to play five Australian dates as part of their WorldWired Tour with Slipknot, followed by a four-show stint in New Zealand. But they were forced to pull out of the gigs after frontman James Hetfield re-entered rehab to treat his addiction issues.

Announcing the news in a statement online, the band reassured fans: “All tickets purchased to the shows in Australia and New Zealand, including Enhanced Experiences and Black Tickets, will be fully refunded.”

Furthermore, Ticketmaster officials, which issued tickets for Sydney, Melbourne, Perth and Brisbane, claimed refunds were expected to take between three and seven days.

But after an extended delay, dissatisfied fans took to social media to demand their refunds, with one writing: “@Ticketmaster_AU any idea when the refund for Metallica will go through? It’s been more than the indicated 10 days now.”

“Hey @Ticketmaster_AU how long until we get our refund for Metallica/Slipknot tickets??”, another penned, while a third fan raged: “Still no refund for Metallica? How slow is this process? Getting beyond a joke now.”

A representative from the site reassured disgruntled users they were “working as quick as we can to get your money back to you”, but that wasn’t enough for some, with one user labelling the situation “a farce and disgraceful effort”.

The tour has been postponed indefinitely as it is unknown when James will be discharged from rehab. The musician previously went to rehab in July 2001 to treat alcohol issues and got sober in 2002.