A gang of youths wearing balaclavas dragged a man into an alleyway before stealing his phone and assaulting him.
Police are appealing for witnesses to the violent robbery which took place in an alleyway off Queen Street in Rushden town centre on Tuesday, February 5.
A police spokesman said: “At around 9.45pm, a group of five male youths dragged a 20-year-old man into the alleyway and demanded his mobile phone.
“The man handed over the phone and was then assaulted.
“The descriptions of the offenders are vague but it is believed they were all wearing black balaclavas.”
The spokesman added: “Anyone in Rushden town centre that night who recalls a group of youths wearing balaclavas are asked to contact police.”
Witnesses to this incident, or anyone with information about it, can call Northamptonshire Police on 101 or information can be given anonymously to Crimestoppers on 0800 555111.