Baton-wielding police clashed with protesters yesterday as an anti-arms demo erupted into violence.

About a dozen people were injured as skirmishes flared during the demo – the latest in a series aimed at EDO/ITT, the Brighton-based weapons component manufacturer.

The main flashpoint occurred on Lewes Road, by the junction with Home Farm Road in Moulsecoomb, as hundreds of protesters came up against scores of police.

Officers closed both lanes of Lewes Road just after 1pm and prevented most of the group from moving south of the viaduct, which crosses the road.

Pepper spray was used on the crowd as it surged forward, attempting to break through the ranks of police. A number of people were hit with batons and needed first aid.

There were also other minor clashes around The Level as a small number of protesters managed to make their way into the city centre.

Traffic around the junction of Gardner Street and Church Street was brought to a standstill for a short time as demonstrations took place.

There were reports of a similar situation at the Clock Tower and near the Palace Pier.

A handful of arrests were made.

Assistant Chief Constable Jeremy Paine criticised those involved in the demo.

He said: “There was clear intent to use violence and cause damage evidenced by the high level of tension among the demonstrators and articles observed and seized by police.

“Disruption was caused to citizens and motorists by a large gathering of protesters on the main A270 Lewes Road leading into the city.”

Hundreds of officers from across the country, including from the Metropolitan Police, Hampshire and Surrey, were deployed to oversee the protest.

It got under way just after noon, with protesters marching down Lewes Road from Falmer station.

They intended to arrive outside the EDO/ITT factory on Home Farm Road but were outflanked by a ring of steel formed around the building by several rows of police, fences and dogs.

It was an entirely different tactic from the one used during a similar demo on June 4, which led to violence when protesters were allowed right up the factory gates.

A spokesman for the Smash EDO group which organised the demo said: “Right from the word go police were basically saying, ‘We’re going to destroy you’. It was a completely disproportionate response.

“We were outnumbered but today has been a success because we’ve managed to get the message out there and show we are prepared to stand up and be counted for our beliefs.”

He confirmed that further highly publicised demos would be held in the future.

The number of officers present at the demo was criticised by Sussex Police Authority member Ben Duncan, who said: “There is a perception, rightly or wrongly, that the police do not have the resources to police our neighbourhoods properly and people are worried about crime as a result.

“Clearly they do not have a problem with resources at all if they can muster this many officers.

“In my view these protesters did not present a real danger and did not warrant this many police officers.”

Lionel Barnard, chairman of the police authority, disagreed.

He said: “We would be expected to make an appropriate response and take measures against this sort of demonstration. I believe that is what has happened.”

Mr Barnard said the overall cost of policing the demo would not be known for a number of days. However, the figure is thought to run into tens of thousands of pounds.

Motorists using Lewes Road and the surrounding areas faced delays for the duration of the protests.

Lorraine Wilson, of Lewes Road, said her granddaughter was late being picked up from St Martins School, in Hartington Road, because her mother could not reach her.

She said: “I had to walk down and pick her up because her mum couldn’t get through the demonstration.

“As I walked through there were a lot of people, older people particularly, who were very scared.”

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