A tree has been badly damaged.
Some mindless idiot has broken it.
What you can do
The trees in streets and parks are the property of, and are cared for by, Southwark Council. Their Tree Section does a pretty good job, so phone the council as quickly as possible to report the damage. They will come and check it and will replace the tree if necessary. You can contact the Tree Section through Southwark’s 24 hour call centre on 020 7525 2000.
You will be surprised at what the Tree Section does. See their web page.