Two friends were assaulted when they went to the aid of two women who had been attacked by a gang of thugs.
The friends saw three men push the two women to the ground in Mill Street, Oakham, in the early hours of last Saturday.
When they went to help the women the three thugs turned on them too.
One of the men was punched and kicked while he lay helpless on the ground. His friend suffered a serious injury to his face and was taken to hospital for treatment.
The attack happened 3am on Saturday.
Police appealed for witnesses today.
Detective Constable Sarah Walker said: "I am keen to speak to anyone who was in the area at the time.
"I know there were a number of people in the area who have not yet come forward and spoken to police.
"You may think the information you have is trivial but it could really help with our inquiries.
"I am particularly keen to trace the two women who were pushed to the ground in the incident. They could have important information."
Contact Det Con Walker on 101 or Crimestoppers, which is anonymous, on 0800 555 111.
