A group of hoodies have been caught on video mugging an injured youth they had apparently gone to help.
The boys who filmed the incident from a nearby roof watched in disbelief as the events unfolded.
The young man, who appeared to be bleeding, is seen lying on the ground when a number of hooded youths approached him.
Surprised comments from the observers can be heard as the group help the teen, who was clearly dazed and confused, to his feet.
"Are they actually helping him up? Oh my God," the boys are heard to say as he stands up.
However, their initial scepticism proves to be well founded when an older man opens and rummages through his rucksack.
Others quickly join in, including the youth who had helped the boy up, apparently searching for items to steal.
The boys recording the act are heard saying: "Oh! He just took something from his bag... monsters!"
Still in a state of shock, the injured teen was not initially aware of what was going on behind him.
By the time he turned round the contents of his bag had been taken and the robbers walked away, throwing the unwanted items to the ground.
This incident is one of many unprovoked attacks that have taken place in the capital and in other cities over the past three nights.