Police have issued a stark warning about their zero-tolerance policy on illegal raves after more than 300 party-goers trashed a farmer's field outside Norwich.

Eastern Daily Press: Workers clear up after a rave at Horstead on a field owned by Wroxham Home Farms.PHOTO BY SIMON FINLAYWorkers clear up after a rave at Horstead on a field owned by Wroxham Home Farms.PHOTO BY SIMON FINLAY (Image: Archant 2011 0)

Six people were arrested at the 18-hour rave near Horstead at the weekend, which landowners fear will cost thousands of pounds to clear up.

Officers seized vehicles, a marquee, a generator and scaffolding from organisers, but the broken glass, needles and drug paraphernalia left behind could stop the field from being used for crops.

Police have called for the public to be vigilant as warmer weather and the longer days create ideal conditions for unlicensed music events.

Andrew Murdo, farm manager at the Wroxham Home Farms estate, where the event took place, said the ravers began turning up at around 10pm on Saturday night and did not leave until 4pm on Sunday afternoon.

He and his colleagues called police and stayed to monitor the ravers to make sure they did spread any further across the land.

'They were all high as kites,' he said.

'There's going to be a massive clear-up, and a massive clear-up bill. It will be many thousands of pounds. I think we will have to take that on the chin.

'But we will need to take a view as to whether we can grow potatoes in that field again. There were needles and broken glass everywhere, and the metal canisters of nitrous oxide that they had been using to fill balloons.'

Police arrived after the rave had started and used the police helicopter to monitor it until its end.

Mr Murdo said he and his colleagues had circled the area in tractors on Sunday afternoon in an attempt to pen in the last of the ravers.

'There were about 400 people there, and we didn't know if they were going to stay there, so we started to cultivate the fields to keep them in.

'The police had to let it run – there were hundreds of people at the rave, and about half a dozen police men.'

The organisers of the rave were clearly well prepared, he added, and had delivered and set up a marquee and generator in the field.

'They were very well organised and I think someone must have been there to do a reccie. They had done their homework, to be fair to them.'

Four people were arrested in connection with organising an unlicensed music event and two on suspicion of theft and possession of drugs. They have been questioned and released on police bail while enquiries continue.

Superintendent Paul Sanford, who led the operation, said: 'There is a zero tolerance approach to unlicensed music events in Norfolk, and this was reflected in the positive action taken to seize equipment and vehicles and arrest those suspected of organizing this event and committing other offences.

'With the rave already under way when officers discovered it, the safest way to deal with it was to monitor it and restrict any more people from attending.

'The rave was in an isolated area and we received only one call from a member of the public on Sunday. Whilst monitoring the rave we worked with the landowner to keep them informed of our actions.'

Norfolk police were called to deal with several large raves last year, including one at Thetford Forest on the weekend of the Jubilee, where seven people were arrested, and another in Gillingham, near Beccles, on July 15, when 10 were arrested.

Officers in King's Lynn came under fire online after posting a YouTube video of them smashing up sound equipment they had seized.

But Nick Dean, chief superintendent for Norfolk, said the zero-tolerance approach would continue.

He said: 'Illegal rave organisers have little concern for the health, safety and welfare of those attending the event, for the local residents, who are adversely affected by the noise, rave-related anti-social behaviour and the impact on the environment, or for the landowner left with litter and damage.

'We will maintain a hard line against anyone organising such event and we will prosecute and seize the equipment and vehicles of those found to be involved in their organisation.