The group decided to try and find an open area to have a meeting to form a consensus on what to do next (how to avoid ending up totally immobile in the queue to join the "demonstration"). There was no way to return into the meadows (because the flow of people where moving behind them), so the group walked, calmly toward a side street which opened out into a paved area near the university. At this point the police began to overreact, deploying a number of officers (probably around 30) from nearby vans, who came up behind the group - preventing them from returning to the meadows.
The group reacted to this by attempting to walk up to the main road, many at the front of the group expressed the intention to walk down the main road and get back on the march. The police, however, had other ideas - they deployed a line ahead of the group preventing them progressing any further. Frustrated by this, and finding themselves blocked from the front and the rear, a sizable proportion of the group attempted to push through the police line to the front. This was a mass push, I did not see any weapons used, or any attempt to hit or strike (either from the police or members of the group).
The police line nearly broke, but was reinforced and managed to hold. Spotting another way out, the group walked calmly toward some steps leading between two university buildings into another street (which was full of buses). The group proceeded down this street, and into a road at the end of it, still attempting to get back onto the main road to join the march.
At this point more police started to arrive. In self defence the group started to take large bins from the side of the road and turn them over. This was to try and prevent police vehicles from getting in among the group. A small number of police charged the group with batons drawn, causing it to retreat rapidly back toward the road containing the buses. In the slight panic, several of the group where forced through the edge of a seating area outside a cafe (there where metal barriers in the road).
Between leaving the road with the buses, and being forced back into it, around a half to two thirds of the group apparently escaped.
The police then blockaded both ends of the road, trapping approximately 80-100 people (not all where originally in the group). There where legal observers, a medic and several journalists present.
After deploying police in full riot gear to block the end of the road, the police seemed to realise that the group did not pose a threat, and replaced them with non-riot police. A group of police in boiler suites with gloves and no visible numbers where deployed to block the end of the road closest to the meadows. The other end was blocked by police in hi-vis jackets.
Some people, including several journalists where allowed to leave by police. The medic was allowed apparently free passage into and out of the cordon.
After some negotiation, the police made an offer to the group to let them rejoin the march as a block. After some discussion, the group reached a consensus that if there where no searches, and the group was allowed to remain as a block, they would comply.
After quite some time (20 minutes) the police decided that they would escort the group back to the meadows. By this time solidarity, including clowns, had gathered nearby. The group allowed the police to form a tight cordon around them, between the two rows of buses. Eventually, the group was escorted down a small road to the left of the buses (when facing the meadows).
This took the group through a narrow gap between two walls. There was some concern when, on turning a corner, the group saw the road ahead passing a small car-park with the boiler-suite police standing looking on, and several vans. The group stopped, until the police explained what they where going to do - the group where escorted round a corner before the boiler suited officers where reached.
Coming to the next sharp corner, the police stopped the group. After some time, it became clear that the solidarity had blocked the road ahead. The group where kept in the narrow road, surrounded by police holding each others belts, for approximately 45 minutes. They where in direct sunlight with no shade the whole time.
The police offered to let the group go in groups of three, with "limited" searches of people "suspected" of carrying weapons. However, many in the group had now lost trust in the police, and refused to comply. None of the group left at this point. After further negotiation, and a failed attempt by some members of the group to make reach a consensus on asking the solidarity to move back slightly. The police decided to use powers under section 60 to force the group to remove hats, face coverings and hoods - and make the group leave one at a time, and be subjected to searches. Having expended a lot of energy, and been kept in the sun with no food or access to toilets for nearly 3 hours most of the group felt unable to resist anymore. At least one person was arrested, apparently for refusing to remove a face covering. The police also removed a chain, which had been in use for holding up a banner, from the floor in the middle of the group.
Water was provided by someone to the group whilst they where being held between the buses.
Despite the harassment, the group remained good natured, drumming with many dancing until their strength ran out. Then sitting quietly on the ground trying to deal with the heat.