Officers investigating a robbery in Long Eaton are appealing for witnesses.
The victim, a teenage boy, was approached by two men as he walked near the bridge over the canal in West Park, Long Eaton, at around 7 pm on 10 May.
The men demanded he hand over a silver chain he was wearing, before threatening him and stealing two silver chains, a Nike zip-up jumper and a black Trapstar windbreaker coat.
The first man is described as being around 5ft 10ins and of a stocky build. He was wearing a balaclava, black tracksuit, black jumper and gloves. The second man is described as being 5ft 3ins tall, and was wearing a full mask on his face, a black hoody, black jogging bottoms and white latex gloves.
Anyone who has any information is asked to contact Derbyshire Police on 101, quoting the reference 23000283239.