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The march from Liverpool Street started at 11am with pleas from Charity Sweet, 42, for a kiss from one of the officers escorting her group to the Bank of England.

The mood was cheerful and calm.

Within an hour her group had converged on the bank and met up with thousands of other protesters coming in from all angles of the City.

Stuck in the middle was a single line of officers in normal attire. For several minutes everything was fine and the crowd had an almost carnival atmosphere.

To the side officers stood on the high steps of the Royal Exchange keeping an eye on proceedings. Then the crowd surged forward and the officers in the middle were completely outnumbered and overrun.

Their helmets were stolen from their heads and thrown into the crowd amid much cheering as bottles, cans and sticks rained down on them.

The officers could not go forward or backwards, their only route of escape was to be hauled out of the crowd by colleagues on the steps of the Exchange.

Reinforcements were quickly brought in to Threadneedle Street to shore up the crowd. But there did not seem to be enough.

They tried to create a sterile zone of several yards between two banks of officers, roughly pushing people out the way.

As the crowd pushed towards the Royal Bank of Scotland truncheons could be seen raining down on the front line of protesters.

But it was to no avail. The crowd reached the RBS and smashed the windows as smoke bombs were let off. Fifteen police horses brought in to restore control were pushed back by the crowd.

Within an hour police had regained order after bringing in dogs and hundreds more officers, all in helmets and carrying shields.

Were the police unprepared for the violence? After months of planning it certainly seemed unwise to allow a single line of officers to be sandwiched between thousands of protesters.

But after they were extracted it appeared that the police lost control of the situation, albeit for just a few minutes, but enough time for the violent element within the crowd to smash the windows of the bank.

Ironically, as the march went past the bank first time round, a line of police officers stood outside it but after the protesters passed they left.

It is easy to accuse the police of being heavy handed, but standing just feet away from them it was easy to see and hear the abuse they came under from the hardcore element within the crowd.

They were spat on, hit and had vile abuse screamed into their faces from inches away. But does this give them the right to indiscriminately hit anyone in their way?

It seemed that once officers got orders to push forward anyone in their way just had to be moved. On the one hand this is understandable, because if they stood and debated the merits of what they were doing with everyone, nothing would get done. But it would also be nice to see a bit of understanding from officers for the innocent caught up in the mayhem.

As the afternoon went on the police cordon increased in size while the main, violent protesters were kept in a tighter cordon, eventually being let out in dribs and drabs.

The consequence of this type of operation is that innocent, peaceful protesters will be caught up in the cordon for hours.

Police say that there is no better way of doing it – they cannot have known trouble-makers allowed to wander around the City, meeting up with others bent on causing trouble.

As of 3am yesterday 86 people had been arrested, three for assaulting police. The number will rise in the coming weeks as police study CCTV and photographs and identify the ringleaders.

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