Police are appealing for witnesses or anyone with information about a robbery in Chelmsford to get in touch.
A 30-year-old man was walking through an alleyway between Oliver Way and Varden Close when he was approached by two men at 3.25am on Christmas eve.
The victim was then punched and fell to the floor before the men then rifled through his bag and stole his possessions.
One of the attackers is described as black, 5ft 10in tall, of large build, and aged between 20 and 30.
He was clean shaven and was wearing a flat peak cap, trainers and a black bomber style padded jacket.
The second suspect was white, 5ft 10in tall, of medium build, and also aged 20 to 30.
He was wearing a grey hat and black jacket.
PC Warren Joseph said: "The victim believes he heard someone shouting at his attackers during the robbery and this disturbed the men and they ran off.
"We have not yet been able to trace this person and I would very much like for them to get in touch."
Anyone with information can call PC Joseph at Chelmsford Police Station on 101 or call Crimestoppers anonymously on 0800 555 111.