Drivers in a Berkshire village are being stopped by police investigating an attack in which a man was beaten unconscious on his doorstep.
The 50-year-old victim spent Christmas in intensive care after the attack in the courtyard of his home in Arborfield on 20 December.
Police said he remains in a coma in a serious but stable condition.
Officers were stopping motorists on the A327 Reading Road to try to trace possible witnesses.
Det Sgt Pete Tomlinson, of Thames Valley Police, said: "I would like to reassure the public that this is an isolated incident and people should not be concerned."
Two men arrested in connection with the attack have been released on bail pending further inquiries.