Police are investigating a paramiltary style attack on a teenager in the in the Gartan Square area of Derry just after midnight on Saturday, June 10.
Chief Inspector Alan Hutton said: “The assault has all the hallmarks of a paramilitary-style attack, with the assailants all wearing masks.
“These attackers set upon a vulnerable 15 year old boy with iron bars – and the victim sustained a number of broken bones as a result.
“Anyone who has information that could help with our investigation should contact detectives at Strand Road, using the non-emergency number 101 and quoting reference number 28 of 10/6/17.
“Alternatively, if someone would prefer to provide information without giving their details they can contact the independent charity Crimestoppers and speak to them anonymously on 0800 555 111.”