At around 3.50pm on Friday 1 September 2023, a man was approached by three other men in an alleyway between Main Road and Farningham Road railway station, South Darenth.
One of the suspects reportedly threatened to spray the victim with an unknown substance and took his watch.
The men allegedly left the scene through the adjacent fields.
One of the men is described as being in his mid-30s and six foot tall, with brown hair and brown eyes. He was wearing grey tracksuit bottoms and a matching grey hooded pullover with pockets. He was carrying a dark blue, plastic sports bottle at the time of the incident.
The other two men are described as being in their mid-20s, one of whom had shoulder length black hair and was wearing dark clothing.
Anyone with information should call 01474 366149, quoting crime reference 46/157174/23.
You can also call Crimestoppers anonymously on 0800 555111 or complete the online form on their website.