Two men were knocked unconscious in an attack at a bus stop in Rotherham.
The 44-year-olds were at a bus stop opposite the Little Mester pub on Nursery Road, North Anston, when they were approached by another man who punched them both.
They told police they both lost consciousness.
Police said they were both taken to hospital, one with serious injuries.
The suspect was white, in his mid 30s, around 5ft 10ins tall, with dark short hair.
He was wearing dark coloured jeans with a two tone sweater.
It is believed that the suspect was in company with a woman with blonde hair who was wearing a dark coloured dress.
Witnesses should call South Yorkshire Police on 101 or Crimestoppers on 0800 555 111.