Pedigree cat theft is in the increase - many will be sold illegally, some kept by the thief, some traded for their pelts. The US has legislation covering trade in fur products which get DNA tested, but the UK lags behind, especially with fashion items and fluffy toys sold as souvenirs, most of which are rabbit. China is the major exporter of cat fur products but several other countries are also involved and the UK is included. I thought about putting a link to a video about cats being traded but it's too disgusting to watch.
The bin bag of cats' heads could have been planted as a malicious act.