Kent police said the victim, who is in his 20s, was walking alone on Friday when he was dragged by the arms into a local park by two men.
Officers want to speak with anyone who may have witnessed the incident or knows the identities of the suspects.
A Kent police spokesperson said: “Officers are keen to speak to anyone with information about the incident or who may know the identity of those involved.
“They are especially keen to speak to a man who was witnessed aiding the victim and taking him back to an address in the North Holmes Road area.”
The incident is reported to have happened between Old Ruttington Lane and Falala Way at about 9.30pm on Friday night.
The attackers were described as black, and witnesses were asked to call Kent Police on 101 quoting reference number 22-1399.
Anyone who may have information can also contact Kent Crimestoppers anonymously on 0800 555 111.