Police are appealing for witnesses after two 16-year-old boys were attacked by a group in Royston on Friday last week, leaving one with a serious head injury.

The incident happened at about 8.45pm in Fish Hill, where the teens were set upon by two or three youths.

Both boys were injured and one was struck several times to the head and body with what police believe to be a baseball bat.

Investigating officer Det Sgt Carolyn Taylder said;”it was unprovoked attack left one victim with skull fractures, for which he has had to undergo surgery.”

The attackers were described as having their faces covered, possibly with balaclavas, and were wearing hoodies.

Both boys were taken to Addenbrooke’s Hospital in Cambridge and have since been allowed home.

Det Sgt Taylder added: “I’m appealing for anyone who may have seen an altercation involving two groups of teenagers or may have seen anyone fleeing the scene, or believes they know who is responsible for this attack to contact me via non-emergency number 101, quoting crime reference G4/16/923.”