A petition to remove the U.S. rock band Metallica from the Glastonbury Festival has been launched by angry fans who took offence at lead vocalist James Hetfield’s bear-hunting association.

Hetfield is a member of the National Rifle Association of America, and will be narrating an upcoming TV series on The History Channel called “The Hunt.”

The program will premiere on June 8 in the U.S.

His association with hunting doesn’t sit well with animal rights activists. One music fan has set up a petition to ban the group from playing at the Glastonbury Festival in Somerset, England.

The Facebook page “Remove Metallica from Glastonbury Festival for their support of Bear Hunting” has already attracted over 20,000 likes, while the online campaign has already reached 6,088 signatures as of the time of writing. It aims to reach 7,000 signatures.

Creator Richard Fraser claimed that Metallica’s inclusion will just tarnish the music festival’s reputation.

“This is a cruel and abhorrent thing to do. Killing animals for food is one thing. But killing for so called sport is wrong,” the petition reads.

The site is addressed to Glastonbury organisers Michael and Emily Eavis.

Hunting animals for sport has no place in the Glastonbury ethos,” one petitioner wrote.

“No one who condones the hunting and killing of wildlife for sport (and in such a public way) should be allowed to be endorsed,” another added.

Another petitioner reasoned out, “By allowing Metallica to play at Glastonbury, the festival organisers are sanctioning hunting. This sick individual and his band should be removed from the line up immediately.”

Glastonbury Festival was launched in 1970, and was inspired by the hippie culture and movements. For 2014, the festival will be held from June 25 to 29.

Metallica will be headlining the event, as well as Kasabian and Arcade Fire. Dolly Parton, Jack White, The Black Keys, Lily Allen, Ed Sheeran, Lana del Rey, and Robert Plant are also playing on the main stage.