Stanley Pugh, the farmer who owns the land, intends to apply for an injunction to remove the travellers if they remain after today. Farmers have claimed that dogs have been sheep-worrying, animals have been stolen and others mutilated, and fences ripped up for firewood. At least 18 people have been arrested for drugs offences and theft.
Dyfed-Powys Police has cancelled all weekend leave. Officers, assisted by a helicopter, patrolled the site, but they do not intend to break up the festival, which they hope will disperse after the weekend. Road checks were set up and several people reported for having defective vehicles. Officers also turned away vehicles carrying large music sound-systems.
The festival came as a surprise to the police, with most of the travellers arriving overnight from Cheshire, Derbyshire and the Welsh border. The site was used for a similar gathering about five years ago.
Mobile toilets, a water supply and large rubbish containers had been placed on the site by Powys county council, said police.
Chief Inspector John Davies of Dyfed-Powys Police said: 'We hope the festival will break up after Sunday - it's not practical to forcibly eject so many people. My main concern is the potential effect on public health as the site has no proper sanitation.'
The Assistant Chief Constable, Eifion Pritchard, said police would block any attempt to move on to Llanbister Common, near Llandrindod Wells, where hippies held a festival last year.
Farmers have spread tons of manure and slurry across the common to deter any mass gathering.