Dyfed-Powys Police officers are urging caution following Sunday's illegal rave near Llandovery.
Around 400 people attended the event near Halfway Forestry, Llandovery, with many travelling from as far afield as Devon and Gloucester.
Police began receiving calls in the early hours of Sunday morning, enabling officers to attend the scene promptly.
A 22-year-old man was arrested and taken into police custody after failing a drugs swipe as he attempted to enter the site.
Now police are urging landowners and residents of rural areas to report any unusual activities which could result in further illegal raves taking place.
Meanwhile Dyfed-Powys Police have commended residents for the way in which Sunday’s illegal rave was handled.
“Once again we want to thank the local community for alerting us to this gathering and for being our eyes and ears,” commented Inspector Dawn Fencott-Price.
“As a result, we were ale to take a practical and safe approach and deal with it effectively.”
The rave was cleared of all vehicles by Sunday afternoon however Dyfed-Powys continued to remain on site throughout the day, meeting up with local residents and providing reassurance.
“We know from our past experience that raves can often cause a great deal of anxiety to the people who happen to live in whichever communities they may be taking place,” added Inspector Pencott-Price.
“And if they’re not dealt with swiftly, they can be very difficult to stop because of the sheer number of people involved.
"It’s also worth remembering that the police have to spend a considerable amount of time and money in ensuring that the site has been adequately cleared afterwards.”
The police are asking residents that any types of suspicious behaviour that could relate to illegal raves should be reported to police online at https://bit.ly/DPPContactOnline, by emailing 101@dyfed-powys.pnn.police.uk, or by calling 101.
Things to look out for include an unusual number of vehicles that suddenly appear in the locality such as camper vans and trucks.
Illegal trespassers may recce sites in advance while landowners may be approached by people seeking to hire land and asked if they could hire if for more acceptable activities such as gymnkhanas or scout camps.
Social networks make it easier for organisers to spread the word. Rave attendance numbers can grow hugely in short spaces of time, and locations can change quickly.
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