Detectives are investigating the circumstances surrounding a potential series of robberies in Chelmsford.

One attack happened in Bunny Walk at the side of the Riverside Retail Park at 6.30am on Tuesday.

A 19-year-old man from the area had been walking along the bridge when he was accosted by a group of people who threatened him with a knife, punched him and then stole his mobile telephone.

Officers attended and recovered a knife at the scene. The victim declined any medical treatment.

Officers later arrested three local boys aged 14, 16 and 17 before releasing them on police bail until August 8 pending further enquiries.

Officers are also investigating an incident in nearby Hill View Road in which a 19-year-old local man was threatened by three bottle-wielding boys at 1am on June 21. The man ran off, uninjured.

During the course of their enquiries, detectives have been told that there have been other, similar robberies in the area but have had none reported to them.

Anyone with information in connection with a recent robbery near the Riverside Retail Park is urged to contact detectives at Chelmsford police station on 101.