The injured, which included three Party activists, five hardened political journalists and two old ladies who thought they were attending a jumble sale, were all taken to the A&E Unit at Guys' Hospital*. All those hurt in the incident were treated for exposure to toxic futility, and subsequently discharged - though one has since been returned to hospital having contracted MRSA during their treatment.
The incident occurred approximately fifteen minutes into the Lib Dem presentation of their Manifesto, when several members of the audience reported symptoms of an existential crisis, sparked by their presence at the launch.
One attendee said, "it was awful. Vince Cable had done his usual Nostradamus bit, as usual, and had actually spoken quite well. A couple of the journalists in the front row had been so excited that they'd stopped snoring. Then Nick Clegg got up and started speaking, and that's when it all went wrong.
"Within a couple of minutes, the sense of complete hopelessness filled the air. I mean, forget the Manifesto - he could've been reading a Mr Men book for all the difference it'll make to the Election. I just started thinking, "Oh God, why am I here? What's the point, really, when all's said and done?", and that's all I can remember until I woke up in the ambulance."
Sources close to the Lib Dem leadership confirmed that Mr Clegg had, in fact, been reading extracts from 'Mr. Nonsense', after an unfortunate mix-up the previous night had led to his children enduring 45 minutes of specious and meaningless tax waffle in lieu of a bedtime story. However, the spokesman insisted that given the Lib Dem's chances of power, it really didn't matter what Mr Clegg read out, as nobody outside the party would be listening anyway.
A spokesman subsequently confirmed that there had been 'an unfortunate incident', but strongly denied those hurt had been suffering from the recognition of an utterly hopeless cause, instead insisting that the injured had merely been 'swooning at the power of Nick Clegg's rhetoric'.
The Electorate was too disinterested to comment.
*and subsequently transferred to the nearest Accident & Emergency Unit that hasn't been closed down yet, just outside Leicester.