Fallen Tree Makes a Home

Sometime between January and October 2005 one of the trees in Aleit Park (next to our flat) suffered storm damage and about half the branches fell down. In spite of repeated requests by various parties, the branches have still not been removed.
Why kick up a fuss about a damaged tree, even if it is in a park? The reason is simple it has now become a temporary shelter for several homeless people, who arrive at around 10pm and leave at 5am, to avoid arrest.
This is all they leave during the day: a packet and some cardboard at the base of the tree. They hide the rest of their stuff in the stormwater drain nearby, as shown here. Their stuff is jammed between the water pipe and the roof of the bridge, and there is a blanket handing over the pipe, presumably to dry out.
On the one hand I feel sorry for anyone who doesn't have a place to stay. It must be pretty grim living out in the open when it's pouring with rain or freezing cold. But on the other hand the area is a park, and if they move in permanently it wil be almost impossible to evict them. If this happens the value of our property will fall, with the obvious financial implications for our bond.
What really gets me is the complete lack of response from the City Parks Department. The building owner contacted them earlier in the year, and has now given up phoning them. Last month Penny sent faxes and made phone calls, and still no response. I've logged a call with the City Council, reference number 0122/20/11/2006.
I understand it is an offence to cut the tree down. I wonder what it will take to get the Parks Department to trim the branches? A law suit? A formal complaint to the Mayor? If we take the law into our own hands and have it cut down, can we sue the council for the costs? The mind boggles.

Update: Tree Inspection Time | City Parks Hard at Work | Joburg City Parks web site