Comedian Peter Kay was ushered off stage mid-performance and the audience was evacuated after a “potential suspicious bag” was found.
Police said a 19-year-old man is being held after the show at the Utilita Arena in Birmingham was halted on Friday evening.
Witnesses said that two members of staff came onto the stage about 45 minutes into the performance, whispered into Kay’s ear, and then escorted him off.
Steve Aspinall, who was at the gig with his wife, told the Press Association: “Two guys came on, one with a mic and headphones, one guy whispered to Peter Kay and then he and Peter Kay shot off down the side.”
He said the audience was told to look for security guards and listen out for any announcements.
“To be honest, I thought it was part of the show at first,” Aspinall, who lives in Bideford, Devon, said.
“It was a strange atmosphere, eerie, just confused really (about) what was happening.
“But it was alright and everyone was calm and left quite quickly with no panic.”
Miranda Richardson, 52, a pub landlady from Northampton, said: “It was very swift.
“One minute (Peter Kay’s) on stage and the gig is great, then two of the event team walk on stage straight to him, quick word and he’s ushered off.
“The staff tells us due to unforeseen circumstances we all have to evacuate the arena straight away.
“Staff helped get people out and it was calm and swift. We heard very quickly someone had claimed a bag had been left somewhere.
“No messing, it was just all out.”
West Midlands Police said the venue is being searched.
A spokesperson for the National Exhibition Centre (NEC) said: “Utilita Arena Birmingham has been evacuated as a precaution on the advice of West Midlands Police after a potential suspicious bag was found nearby.
“The safety and security of our customers and colleagues is our highest priority. We can confirm everyone was safely evacuated and that the venue is secure.
“Ticket holders will be contacted directly in due course.”