Liberty X found fame through the ITV talent show Popstars

The band were singing their Children in Need hit A Night to Remember at the May Ball in Aberystwyth on Saturday.

A cloud of smoke engulfed the university's venue and the band and 1,000 students had to be evacuated.

People were allowed to return after 50 minutes but Liberty X failed to reappear.

Firefighters were called to the university's arts centre where the annual May Ball, the highlight of the students' union social calendar, was being staged.

Revellers had paid �37 to see the five-piece band, as well as Bodyrockers, X-Factor's Tabby Callaghan and Chesney Hawkes.

The smoke became so dense you couldn't see the stage or Liberty X Student Andrew Austin

Aberystwyth Guild of Students' commercial manager Steve Pickup said: "What appeared to be a smoke bomb was set off in the crowd near the stage and near the band's tour manager."

Andrew Austin, 22, a university student originally from Neath, witnessed what happened.

"They were just two minutes into their first song when the smoke bomb went off," he said.

'Jeered'

"There was a lot of coughing and a few screams and a huge cloud of smoke. The smoke became so dense you couldn't see the stage or Liberty X.

"We were told they wouldn't reappear and a few people jeered, but the final act, Chesney Hawkes, did a good job."

Geraint Edwards, the guild's events manager, said it was appealing for information about the perpetrator.

"I'm more annoyed with the individual for doing something so reckless," he said.