Two 17-year-old boys were approached shortly before 9pm by a group of three other teenage boys who demanded they hand over their cigarettes and lighters. They handed over their property and then left the area.

The two 17-year olds later returned to the park, where one of them is believed to have then been assaulted by a group of up to 13 young men. He did not suffer any visible injuries and did not require medical attention.

Both victims had their mobile phones taken from them during this incident. One was a silver Sony Ericsson mobile and the other was a black Blackberry 8520.

Police are keen to identify the group of youths who are believed to have been involved in this incident, including the three boys who first approached the two victims. They are all believed to be black and in their late teens.

PC Sophie Hill, of Bitterne police station, said: “Police are appealing for anyone who was in the area at this time, who may have seen these groups of youths or who may have witnessed the incident take place to contact us. If you have any information which could help police with their enquiries then please come forward.”

Anyone with any information is asked to contact PC Sophie Hill at Bitterne police station on 101 or Crimestoppers on 0800 555 111, where information can be left anonymously. Mini-Com users can call 01962 875000.