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The Lumineers won't be lighting up the Firefly Festival this weekend.  The folk-rockers announced Thursday that an "illness in the band" has forced them to pull out of the Dover, Delaware event, which is scheduled to get under way today. 

A post on the Firefly Facebook page says Ben Harper and Charlie Musselwhite have agreed to take the Lumineers' place.  Rapper Earl Sweatshirt has also canceled his appearance at the festival, and will be replaced by Schoolboy Q.  Meanwhile, the Red Hot Chili Peppers are still on board to headline Firefly's first day, which will also feature performances from Grizzly Bear, the Avett Brothers, Public Enemy, and more. 

Day Two's lineup includes Tom Petty and the Heartbreakers, MGMT, and the Yeah Yeah Yeahs, while Vampire Weekend and Foster the People will help close things out on Sunday.  The full schedule and other festival details are available at

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