A dozen people passed out during a disorientating Brighton Festival performance by two acclaimed authors and a renowned DJ.

The show featuring Irvine Welsh, of Trainspotting fame, Fight Club writer Chuck Palahniuk and DJ Phil Hartnoll, one half of dance-band Orbital, was labelled "irresponsible and dangerous" by some members of the audience.

St John's Ambulance staff treated 12 people who collapsed during the show which featured ambient sounds, flashing lights and visual displays, all arranged to bombard the senses.

The Brighton Festival described the Stories In Motion "multimedia happening" at the Corn Exchange in its programme as: "Transplanting the creative impetus from the desktop to the live arena, the writers and DJs jam back and forth with ideas and storylines to build a unique multi-layered narrative in words, music and images, right before your eyes and ears."

Audiences were only given the warning: "Off the cuff and on the hoof, this one-off collaborative outing is an entirely new concept in storytelling without safety nets. Get ready for freefall."

But people left the concert hall feeling sick and faint and at least six passed out all at the same time during one ten-minute portion of the show.

Before the performance, one member of the security team said: "I couldn't tell you how long its going to be, we'll have to see how many people will throw up."

Extra First Aid staff were drafted in from the Dome to help as security guards began issuing water.

Anne Jeffery, 66, of Old Shoreham Road, Hove, fainted less than half way through the two-hour show.

Her husband John Jeffery said afterwards: "She was fine and we were laughing and she suddenly said she felt light headed. Then moments later she sank to the floor."

Mrs Jeffery said: "I felt very claustrophobic but I desperately wanted to see Orbital. I've never fainted before and still feel sick 15 minutes later."

Writer Irvine Welsh said it was the power of Fight Club author Chuck Palahniuk's story-telling that was making people ill. However, many collapsed before the US writer even spoke.

Mr Welsh said: "The music and images help but it's an amazing reaction to the story - people faint every single time."

Daniel Brace, door security officer, said his team had been briefed on the possible consequences of the show.

He said: "We've taken every precaution and given out warning leaflets and we have St John's Ambulance on site."

Jane McMorrow, festival producer, said about 800 people attended the show.

She added: "Of course it wasn't set up to make people faint.

"It was a real bombardment of the senses and I think we gave a sense of what it was going to be in the brochure."

Brighton and Hove City Council said it had no complaints following the performance on Sunday.