Last weekend's rave in countryside north of Woodingdean, Brighton, was condemned as irresponsible, by police, farmers and politicians.

Those who attended the event claimed it was harmless fun for people who just wanted to party.

Rave organisers will run similar events in Sussex over the coming weeks, playing a cat and mouse game with the police, who are determined to clamp down on disorder.

But unless police receive prior warning of an event it is often impossible for them to stop it happening or break it up.

The raves are never advertised but their whereabouts and timing are spread by word of mouth only hours before the event begins.

News of the location is spread through the local night clubs, among travellers and the student population, and within an hour thousands can be heading for a particular venue.

Last Saturday it was Woodingdean.

This weekend it could be in an empty warehouse near you, blasting deafening music through giant loudspeakers and wrecking the sleep of thousands.

The Woodingdean rave lasted ten hours between 1am and 11am on Newmarket Hill - land which is owned by Brighton and Hove City Council and farmed by Rottingdean farmers John and Martin Carr.

Newmarket Hill leads to the Castle Hill nature reserve, which is a Special Site of Scientific Interest due to the rare plants and insects found in the area.

The events are not always harmless and peaceful. Last weekend two police cars were damaged at a cost of £15,000.

Police had little warning of the event and were only able to monitor the several hundreds drinking alcohol and dancing.

And despite organisers going round the site with large plastic bags to collect rubbish the Carrs claim damage costing more than £500 was caused to the land.

Farmer John Carr estimates the event was attended by more than 1,000 people who arrived in 200 cars.

It is the fourth time in four years Newmarket Hill has been used for a rave.

During past years police have successfully stopped regular raves taking place in Littlehampton, Climping and Patcham.

But this time the ravers timed their arrival at the site between 9pm and 10pm, knowing police were changing shifts and unable to get sufficient manpower to the site to block their entrance.

In fact police only heard of the rave at 4am when they were phoned by motorists and residents in Woodingdean.

Inspector Paul Smith, head of the East Sector of Brighton Police, said: "To stop raves like this taking place we have to be in place early and get enough manpower to the area to block off the site.

"When we got here, there were so many people here that we just had to stand by and monitor.

"It was while the officers were walking round the site the police cars were damaged.

"The area was cleared by midday on Sunday. There was no trouble as people left. So in that sense our policing policy of the event was a success.

"It is vital we get early warning from the public if they see people possibly gathering for a rave. If we had had earlier warning about what was happening at Woodingdean, we could have got enough manpower to seal off the area and persuade people to go away."

Once a party has started, the police do have powers through the Criminal Justice Act, including confiscation of equipment and powers to arrest people openly dealing in drugs.

Local authorities and private individuals are almost powerless to stop a rave once it has started.

Action through the courts would take too long and they would only be able to take civil action beforehand if there was concrete details of the location and time.

Only if a rave went on for a few days would it be possible for solicitors to take action through the civil courts.

However those participating in the raves don't believe they are doing anything wrong.

One of the ravers told The Argus: "We went out on the Downs, had a fantastic time, watched the sun come up and then wandered home in the late morning warmth.

It is quite amusing to find one's evening a subject of intrigue for the whole of the media and of course it's real pity it became public interest because of damaged police cars.

"I wish they hadn't been damaged, and so did almost all other party-goers.

"I didn't go to a rave on Saturday night, I went to a free party".