The Lumineers have cancelled their appearance at this weekend’s Firefly Festival due to an illness in the band. Ben Harper and Charlie Musselwhite, who are on the road in support of their collaborative album, have been added as their replacement.

A message from The Lumineers explains:

It is with great regret that we have to announce that due to an illness in the band, The Lumineers will not be able to perform at the Firefly Music Festival this coming weekend. We were all extremely excited to be a part of this great event and share our music with you, but the health and well-being of the band along with giving the fans the best possible performance remain our top priority. Unfortunately given the circumstances, both of those things would be in jeopardy if we went ahead with our set this Sunday. We hope everyone enjoys the festival and we will be back to see you all as soon as humanly possible.

The Dover, DE Firefly Music Festival kicks off later today. Red Hot Chili Peppers, Tom Petty & the Heartbreakers, Vampire Weekend, Foster the People, Yeah Yeah Yeahs, The Avett Brothers, Passion Pit, MGMT, Dispatch and Calvin Harris are among the other acts confirmed to appear at the three-day event.