What a feeling! But not quite what a group of Kent theatregoers had in mind when they went to the London production of Flashdance last night.

Just minutes after the curtain lifted at the Shaftesbury Theatre, actors were ushered off the stage and the 800-strong audience ordered to evacuate the building.

Fumes were flowing into the Royal Circle where the Kent group of 52, all members of the KM Group Social Club, based in Larkfield, near Maidstone, were sitting.

At first, everyone thought the pungent smell was coming from stage effects but they realised the problem was real when a theatre official came on stage to tell everyone to leave the building.

As audience and actors gathered outside, trying to keep warm on a bitterly cold night, fire fighters arrived.

Forty-five minutes later, a megaphone message said the production would resume. But fire fighters decided it was still too dangerous to allow anyone back into the theatre and at 8.30pm, the performance was cancelled "because of circumstances beyond our control." Ticketholders were promised a refund or a new booking.

The problem was caused by a faulty air conditioning unit that had caught fire and instead of recycling air was pumping out fumes. An official said it was the first time in at least four years that an audience had been evacuated from the theatre.

Mandy Reynolds, organiser of the KMG trip, said: "We had all been looking forward to Flashdance for months and were really disappointed. But it was more important that everyone was safe and I'm hoping we will be able to go back for a future performance."