A man suffered serious injuries during what is thought to have been an attack outside a school in Heckmondwike.
The victim, 48, was taken to Leeds General Infirmary following what police describe as "an incident" at 6.15pm on Tuesday.
It happened outside a school in High Street, and the man suffered serious head injuries.
He remains in hospital today (Thursday), police added.
Anyone with information is asked to contact the police via 101, quoting log 733 of October 11.