Eventually after lashing out at protestors for leaning on the barrier (leaning whilst being crushed by the weight of the crowd), people started dragging away barricades, and the police started attacking people. Around four protestors have been taken to hospital.
The worst moments were when 100 or so more riot police appeared out of Great George Street, seemingly with the task of snatching individuals. Perhaps 200 protestors left the Whitehall barrier to confront them and there were a number of charges and counter-charges between the two groups, all of which were sparked when police snatch squads grabbed individuals and roughly dragged them behind their line.
This is the first time that their have been confrontation with police on a stop war demo, funny that when there is violence the demo gets front news on bbc site.
I will down edit and download video footage tomorrow night, too tried to do tonight.
keep you posted.