The chaoes caused by this mindless act by the police has no doubt pissed off lots of local people, commuters and delegates at the nearby Arms Fare who (if they had come by car) would have had a hell of a job to get out of the area.
Eventually the police brain realised the mess they were making and allowed the party go'ers to at least get off of the A13. They were then forced into a local park.
It must be said that the 3,000 odd coppers and security in the docklands area this weak, having harrased loads of innocent people every day (while seemingly failing to notice the invasion of Excel by paramilitary terrorists from around the world) have failed to prevent protesters from entering the arms fare and hanging a banner on a tank. Job well done...