Mumford and Sons are boycotting a Swedish music festival they headlined at the weekend after dozens of reported sexual assaults.

The band said they were "gutted" to hear of reports of five rapes and more than a dozen suspected sexual assaults at the Bravalla Festival in Norrkoping, south-west of Stockholm, that took place from June 29 to July 2.

In a post on their official Facebook page which was signed by all band members, they vowed not to play it again until security had improved.