Fleetwood Mac bassist John McVie has been diagnosed with cancer, prompting the band to cancel the Australian and New Zealand leg of their world tour so that he can undergo treatment.

“We are sorry to not be able to play these Australian and New Zealand dates. We hope our Australian and New Zealand fans as well as Fleetwood Mac fans everywhere will join us in wishing John and his family all the best,” reads a statement on the band’s website.

Ticket refunds are available to all ticket holders at this time.

Fleetwood Mac recently finished up the European leg of the tour.

Watch: Christine McVie Reunites with Fleetwood Mac On Stage in London