Dumping of dog waste in garden

I've just retrieved 3 huge bags of dog mess from My garden (where my 2 year old daughter plays). This is the 5th/6th time this has happened now over the past month or so. There is a dog foul bin on the other side of my fence (near the little Tesco/ Lerwick croft/ back of Salvation Army car park) I don't know if it's full, but it's often vandalised and broken. However someone has cleared their garden of a lot of poo and taken it to the bin, but then decided to throw it into my garden!!!! This is happening to frequently and Is becoming a health concern. Something needs to be done. Thank you