In a note posted to their Facebook page earlier this morning, Mumford and Sons have shared their anger toward the organizers of Sweden’s largest music festival, Bravalla, which the band headlined last weekend.

“We’re appalled to hear what happened at the Bravalla Festival last weekend,” the band writes. “Festivals are a celebration of music and people, a place to let go and feel safe doing so. We’re gutted by these hideous reports.”

As The Telegraph reports (via Rolling Stone), there were five reported rape cases and a dozen sexual assault instances brought to the attention of Swedish police. Mumford and Sons vowed in their statement to never play Bravalla again until the organizers do more to fight the problem.

“We won’t play at this festival again until we’ve had assurances from the police and organisers that they’re doing something to combat what appears to be a disgustingly high rate of reported sexual violence.”

Another Swedish festival that took place last weekend, Putte I Parken, also resulted in a large amount of sexual assaults being reported, as The Telegraph notes that police were alerted to 35 instances of molestation, but no reports of rape.