Sexual harassment and groping remains a big problem at live music events, promoters and venue owners have warned, after the duo Sleaford Mods said a female fan had been assaulted during one of their shows.

The punk band spoke out after a gig in Bristol on Saturday night, saying on Twitter that they had “had a report of a female fan being groped in the crowd”, and adding: “Touching anyone without their consent is not acceptable no matter how you dress it up.”

We’ve had a report of a female fan being groped in the crowd last night. Touching anyone without their consent is not acceptable no matter how you dress it up. If you think groping women is acceptable don’t bother buying a ticket, we don’t want your money & you’re not welcome. — Sleaford Mods (@sleafordmods) April 7, 2019

Their comments prompted campaigners and promoters to affirm that sexual harassment remains a persistent problem at live music events, calling for venues to do more to train staff on how to deal with such incidents.

Kate Crudgington, who co-runs Get In Her Ears, which started as a radio show four years ago before becoming an online magazine and gig night supporting women, said: “It’s always been a problem, but the reason it now seems like a bigger problem is because women and girls are speaking out on social media and that draws more attention to the issue, as well as providing a level of support for other girls and women to share their stories too.”

She added: “From my experience, I would say it [sexual harassment] is commonplace … I would say the problem is quite pervasive and it takes a certain amount of perseverance to get past it and to not let it affect your attendance or enjoyment of gigs and festivals.”

Freya Gill-Stevens, the promotions manager of the Leadmill venue in Sheffield, said it was a “problem that persists”.

She added: “It’s not just in a music space but also at football matches, anywhere that there is a mass of people and where there is alcohol involved … people cannot keep their hands to themselves, as awful as that is.”

Gill-Stevens said things were getting better in one sense, noting that when women were harassed or assaulted, their attackers were more likely to be called out about it now, with bands making statements after their shows and saying that behaviour is not welcome. “The problem is there but there’s been a shift in how it’s dealt with, with bands speaking out about it,” Gill-Stevens said, adding that the Leadmill had launched a zero-tolerance approach to sexual harassment.

Jen Calleja, the co-director of Good Night Out, a campaign to end sexual harassment and assault in venues, bars, clubs, pubs and festivals, said: “Harassment like this has always existed, and women and LGBTQ people have been talking about their experiences of it for a long time, both privately or publicly. It’s becoming more accepted to talk about these incidents openly … and it’s hopefully becoming more likely that people will be believed and helped.”

She added: “It should be compulsory for venues to have set procedure. A venue will legally have a health and safety procedure but most don’t have a procedure in place for when someone has been harassed or assaulted.”

Dr Hannah Bows, an assistant professor at Durham law school who is researching sexual violence at music festivals, said: “It is really good to see a band taking the lead on sending a clear message that sexual harassment will not be tolerated and perpetrators are not welcome. We need all artists, venue and festival organisers, staff and patrons to adopt the same approach.”

A 2018 YouGov poll found that one in five festivalgoers – and more than two in five of those who are female and under 40 – say they have been sexually assaulted or harassed at a UK festival.

The survey of 1,188 people found that 22% of all festivalgoers, 30% of female festivalgoers of all ages and 43% of those under 40 said they had faced some kind of unwanted sexual behaviour, the most common being “unwelcome and forceful dancing”.