Jake Burns, lead singer and guitarist from the Northern Irish group Stiff Little Fingers (SLF), expressed outrage at the reported incident in a post on social media.
He tweeted: “Apparently a woman was sexually assaulted in the mosh pit at our show in Glasgow last night. To say I am furious is putting it mildly.
“SLF are, and always have been, an all-inclusive band. Regardless of race, gender, sexual orientation or religion, EVERYONE is welcome at a Stiff Little Fingers show and EVERYONE has the right to feel safe and enjoy themselves while there.”
Burns also called out to people who had been in the crowd to check their cameras in case they could identify the culprit.
He said: “Sadly we weren’t filming last night’s show, but enough of you were with your phones. Maybe we can find this guy and report him.” The alleged attack occurred on Sunday evening during the second of the band’s two-night run at the infamous Barrowland Ballroom in Glasgow’s east end.
Other fans and members of Sunday’s audience joined the rock star to hit out at unacceptable behaviour by “vile scum”.
Andrew Standen said: “There’s no place at SLF gigs (or any live music event) for unacceptable behaviour like this. We look after each other, not prey on others.”
Police Scotland said they had received no reports over the allegations.