A couple who were walking along a road in Northampton were stopped by a gang of three, attacked and robbed.
A 15-year-old boy was walking with his girlfriend in Fullingdale Road, Abington, when they were stopped by three men.
Both of them were assaulted, and a green iPhone 5c was stolen. Both victims were punched and kicked.
One of them suffered a broken arm as a result and both were very shaken by their ordeal.
The offenders are described as black or mixed race and in their late teens or early twenties. They were all about 5ft 10in to 6ft, and one was wearing a red hat and a jacket which was partly coloured red.
The three men ran off into the footpath between Fullingdale Road and Broadmead Avenue and then went along the footpath to Grange Road before heading into the park and then into Newby Court. This is where a witness lost sight of them.
A robbery took place at around 8.35pm on Saturday, December 6.
Officers are appealing for witnesses or anybody who has information about the identity of the offenders, or who has been offered the mobile phone (IMEI number 3585 460 5822 8958, serial number F78MK0X2G078).
Witnesses, or anyone with any information about these incidents, can call Northamptonshire Police on 101 or Crimestoppers on 0800 555111.