The victim was walking through the recreation ground on Tuesday 28 September 2021 when he was reported to have been approached by a man he did not know at around 4.40am.
The offender is alleged to have pulled the man off the path and pushed him into a nearby bush, before he punched him in his stomach.
The suspect then went through the victim’s pockets before the man was able to defend himself and then run from the scene.
Investigating officer PC Charlotte Grant said: ‘Due to the time and nature of the incident, the victim has not been able to provide a description of the offender who had his hood up.
‘We would like to hear from anyone in the area who has CCTV overlooking the park or anyone who may have been driving in the area at the time and may have dash camera footage.’
You can also report anonymously to Crimestoppers in Kent by calling 0800 555 111 or using their online form.