Three men approached a girl on a secluded path and tried to rob her.
The incident happened on a path between Rutherford Road and Beecholme Drive, Kennington.
When the trio approached the teenage girl, one man ordered her to hand over her belongings and followed her briefly when she refused.
No items were stolen in the incident, which happened at about 7.40pm on Saturday, and no injuries were reported.
Officers are investigating and are appealing to anyone who saw three men in the area around that time, or who may have domestic CCTV that could assist.
The male who demanded the victim's belongings is described as at least six feet tall, wearing a black face mask and a black coat with the hood up.
Anyone with information is asked to call Kent Police on 01843 222289, quoting 46/32819/21.
You can also contact Kent Crimestoppers anonymously on 0800 555111, or by completing an online form on their website.