Avon and Somerset Police have interviewed a man over comments made during Bob Vylan's set at Glastonbury earlier this year.
The police force said in a statement: "It has been important for us to have a full understanding of any legal precedents, which is a complex process, and therefore over the past couple of months we have been seeking early legal advice from the Crown Prosecution Service (CPS).
"Advice from the CPS was received during the week commencing Monday 20 October.
"Following a review of the advice, a voluntary police interview was arranged to help us progress our enquiries, which was held yesterday [on Monday]."
Voluntary interviews are often used by police to interview witnesses or suspects in cases where arrests are not immediately deemed necessary.
It continued: "The matter has been recorded as a public order incident while we continue to investigate and consider all relevant legislation.
"Voluntary police interviews are commonly used in investigations where an individual agrees to attend and an arrest is not considered necessary, for example on the grounds of public safety or for the preservation of evidence. Attendees are interviewed under caution and have the same legal rights as anybody who is arrested."
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