A delivery driver was robbed at gunpoint when he was lured to a road by someone making a false order for Chinese food.
The victim, from South Woodham Ferrers, arrived in Middleton Row in the town where he was threatened by a man dressed in black and wearing a balaclava.
His assailant had a gun, which the victim thinks may not have been a real weapon, and struck him around the neck with it.
The driver, aged 26, suffered a minor injury in the incident at about 10pm on Saturday.
His wallet containing a small sum of cash and his car keys were stolen, and later found nearby by a member of the public.
An Essex Police spokesman said: "The suspect is described as aged 20 to 25 and of mixed heritage.
"Police believe he may be local as he seemed to know the nearby alleyway and area as he ran off from the scene."
Anyone who was in the area or has any information about the suspect is asked to contact detectives at Chelmsford CID on 101 or via Crimestoppers on 0800 555 111.