Yet more police brutality?

Better than the snippets that are being repeated is the full video of the woman being slapped. Full in the sense that the recording starts unedited 3 minutes prior to the incident and thus one hopes puts paid to all those complaining that we can't see the 'context'.

0:13 A women in a black coat not being able to leave and being gently pushed back.

0:52 she approaches again, but just holds a conversation with an officer

01:12 we catch our first glimpse of the 'villain' of the piece moving forward to talk with another officer and I can catch a glimpse of a minor struggle as someone tries to leave the cordon at that point.

1:19 someone from outside the cordon with a camera walks straight between two officers into the group, the struggle appears to be ongoing and an over the shoulder camera crew has appeared. Our villain has stepped back.

2:14 one camera holding guy bumps into another; looked at first glance as if they were passing something to each other heh. No they weren't.

2:18 we get a close-up of our villain's forearm armour. Very stylish, love the green arrows.

2:42 another gentleman enters from outside the cordon.

2:58 our villain moves forward for another chat with the same officer.

3:11 we hear voice of the guy who could be said to be the catalyst for the event we're about to witness stating that "It's only me though" as the camera pans around we see that he is trying to leave the cordon. He is carrying a rolled up newspaper in his right hand and seems to be talking politely to the police.

3:21 the camera pans across leaving him still talking to the police, and we see yet another person enter the cordon. This is followed by a camera-wielder attempting to leave and being stopped. He lifts his camera to show he's just taking pictures but is still denied the ability to leave.

Meanwhile we can still hear newspaper holder trying to leave "yeah but it's only me" [garble] a female officer is heard to respond "and I'm telling you you're not". We're still looking at the other guy who appears to be trying to hear the response of the officer in front of him. Repetitions of "Yeah but it's only me" can be heard.

3:31 Our villain comes over to stand behind the officers preventing camera guy from leaving. Camera guy appears to give up and moves towards newspaper holder

3:35 Quick camera pan to the right to see newspaper holder being held by the lapels by a male officer and being forced back away from the cordon. He drops his paper. Cries of "Easy Easy" can be heard. He leans forward and down to the right. Another officer moves in from that direction and pushes him upright and backwards. He has been released from any hold and moves back towards the pushing officer and bends down to pick up his paper. He then continues to move forward and takes umbrage at the lapel grabbing officer who then shoves him back.

3:40 At this point the crowd outside the cordon start to jeer and move forward. A camera moves in from the left and our villain starts to order those outside the cordon "Get back, get back"

3:45 The woman appears "What are you doing?" he pushes her back to cries of [garble] F***ing women" She then darts in again with "Your scum".

3:50 Backhanded slap highly audible. Villain "Go away" cries of "Oi". He is then alerted to something on his right (our left) and drops straight into fight/defence posture number one "Get back, get back now"

3:56 He reaches for his baton. Another officer moves in from the left to aid. The women has moved forward and is now standing still before him pointing back to the spot where he hit her. He then whips the baton at her legs and takes her down. This prompts cries of "Scum" and "Man down"

4:17 as other officers move in he heads back to face the cordon. "Shame on you" can be heard.

4:28 another officer moves forward in an apparent attempt to keep back the crowd now formed and does so by talking to them. "Yeah alright...Turn round... there's nothing to see is there"

4:47 Crowd start chanting "Shame on you"

5:01 a Police photographer turns up to film the protesting crowd who now amusingly consist of the ones outside the cordon.

So thoughts. We have a cordon that seems quite happy to allow anyone in, but denies them the ability to leave. Nobody entering appears to be warned that they will be unable to leave. Our cameraman at 3:21 seems almost bemused that he's being lumped in with the protesters.

We see someone who appears to be holding a civilised argument about wanting to get out being manhandled (although as pointed out the camera pans away so we are unsure of his physical actions although no verbal cues seem to be heard until he is grabbed)

This prompts a response from both the people inside and outside the cordon which is handled by an officer attacking a woman.

To put it as I see it from this video the entire incident was prompted by the police over their handling of one person's attempt to leave their cordon.