Four men have been arrested on suspicion of inflicting grievous bodily harm after a man was found lying in a road with a serious head injury.
The 30-year-old Grantham man was discovered in Tilling Close, off Huntingtower Road in Grantham, at around 7.15am on Thursday.
Two Grantham men, aged 23 and 28, were arrested initially, followed by a 19-year-old Grantham man and a 45-year-old man from Sheffield.
All four men have been released on bail until June 10 pending further enquiries.
The victim is described by police as being in a critical but stable condition at Queen’s Medical Centre in Nottngham.