Protesters accused Sussex Police of "massive overpolicing" at a demonstration outside a factory which makes bomb release parts for fighter jets.

More than 40 police vehicles, including vans, cars, motorbikes, CCTV and dog units, surrounded a few dozen protesters holding a celebratory demonstration outside the EDO MBM Technology factory in Home Farm Road, Brighton, yesterday.

Up to 100 police officers on the ground and sitting in vans nearby filmed the group of about 50 protesters arriving at the demonstration and throughout its duration.

The protest passed without arrests.

Protesters, celebrating the lifting of a ten-month injunction which had banned them from demonstrating within half a mile of the factory, said the number of police officers was "outrageous" and a pure show of authority.

Super Intendant Kevin Moore of Brighton and Hove Police, in charge of the operation, said the unwillingness of the protest organisers to tell police what they were planning or how many people might turn up meant he had no choice but to prepare for a worst case scenario.

Police vans were also stationed in streets near Home Farm Road and Supt Moore said more officers had been on standby to join the operation if needed.

Geoff Beuret, 66, who has been protesting against the factory ever since the campaign, labelled Smash EDO, began 18 months ago, said: "It is absolutely outrageous.

"Can you imagine how much this is costing the taxpayer?

"I really don't know how they calculated there would be so many of us when there never has been before.

"We are peaceful and never try and stop traffic so I really don't see why so many need to be here."

Supt Moore would not reveal how many officers had been involved in the operation in total but said: "I policed the event in accordance with the number of protesters that were there and I believe the event was policed proportionately."

EDO MBM, which makes bomb release components for fighter jets used in Iraq, had been fighting for months to get a permanent injunction banning protests within an exclusion zone around the factory but unexpectedly dropped the case earlier this month and agreed to pay hundreds of thousands of pounds in costs to the protesters.

Yesterday was the first time in nine months that anyone had been allowed to protest outside the company headquarters.

Protesters made themselves heard, banging drums, dancing and singing to loud music which blasted out of sound systems.

They also booed and shouted at EDO employees as they left work for the day.

On Monday activists had criticised police for informing them by email they would only be allowed to congregate in one designated spot but in the end a fenced-off area was not used and people were free to stand where they liked, as long as they didn't block traffic.

Sarah Tester, 27, said: "It's a great party-like atmosphere celebrating a huge victory for civil rights in Brighton. The High Court result will hopefully have a huge impact on people's right to freedom of expression around the world."

Smash EDO spokesman Andrew Beckett said: "Although Sussex Police put on a massive display of overpolicing they didn't have a legal leg to stand on and were not able to enforce their proposed pen for us.

"I hope now we will be allowed to freely protest outside the factory in accordance with our democratic rights."