Human defication - 3x in a month

Three times over the past month someone has used this area to deficate during the night. It is just off the road in a small walled off alley. It can be easily accessed from the street and there is no lighting so provides privacy at night. The defication stinks and can be smelt from the road, the person doing it also leaves fouled toilet paper and towels in the garden and on the footpath. Concerning as there is a childrens nursery just a few houses down. I have cleaned it up each time with bleach and water, it has become a common occurance and the area needs a light installed to put an end to it.