A group of five men have been arrested on suspicion of grievous bodily harm after an assault in Lincoln, on September 23.
Police were called after reports that a 19-year-old man from the Leeds area had been assaulted, sustaining a head injury.
The incident occurred on Rosemary Lane, Lincoln, at around 3:30am on September 23.
The man is currently being treated at Lincoln County Hospital for a suspected broken jaw.
A 25-year-old man, a 24-year-old man, a 26-year-old man, an 18-year-old man and a 23-year-old man, all from the Cleveland area, were arrested on suspicion of GBH.
They have been released on police bail pending further enquiries till November 28.
Anyone with any information can call Lincolnshire Police on 101, or call independent charity Crimestoppers anonymously on 0800 555 111.