A man and woman were knocked unconscious when violence flared outside a Sheffield pub.
Detectives said the incident on Blackstock Road, Gleadless Valley, on Friday night started when a man made a comment to a woman as she walked past him, before punching her in the face.
Her friend, a 23-year-old woman, followed the attacker into the Blackstock Pub, where she confronted him.
She was then attacked by another man, and knocked unconscious, as she left the pub.
That attacker then assaulted an 18-year-old man, who was also knocked unconscious, after he stepped in to try to assist the two women.
PC Mary Glenwright said: “This was a nasty and violent attack and I would urge anyone who may have witnessed the incident, or who may have been in the pub or the area at the time to please contact police.”
Both attackers were white and around 5ft 7ins tall.
One was around 45-years-old and was wearing a black bomber style jacket.
The other was around 35, of a stocky build with a bald head and was wearing a dark polo shirt.
Anyone with information should call South Yorkshire Police 101 or Crimestoppers on 0800 555111, quoting incident number 1,085 of March 20.