A 35-year-old Horley man was taken to hospital with a serious head injury after he was attacked in Crawley.
The man suffered what was described as a serious but not life-threatening head injury and was taken to East Surrey Hospital, Redhill, after the assault in Broadfield on Tuesday (January 21).
A Sussex Police spokesman said the victim reported that he was attacked by a boy aged between 12 and 16 shortly before 10pm.
The assault happened in Seymour Road, at its junction with Trefoil Road, in Broadfield Barton.
The spokesman said: “The assault was reported to Sussex Police by Surrey Police from the hospital just before 4am on Thursday, January 23.
“Officers are in the early stages of establishing the full circumstances.”
The boy was described as white, aged between 12 and 16 and of slim build. Anyone with information should call Sussex Police on 101, or email: email@example.com People can also call the independent charity Crimestoppers anonymously on 0800 555 111.