Horses are having there manes plaited (small plaits in mane or tail) manes cut, or small parts of there legs clipped.
Please be extra vigilant and make sure you look for any suspicious behaviour! Red car has been spotted neumourous of times by the scene!
They come back within 3 - 4 days to steal your horse, it could be in the afternoon or night you just don't know, that's why you have to make sure that there is really good security at your yard!
Please post if you have seen any behaviour or have any info or questions!