A fight in a Higham Ferrers pub left a 21-year-old woman needing stitches after she was glassed by a man in an incident described as "a nightmare" by an eyewitness.
One victim was punched repeatedly and another told police they were bottled during the brawl at the Green Dragon Hotel.
According to the eyewitness, three men had come to the pub with the intention of starting a fight "for no reason".
"They were just starting on anyone," said the eyewitness.
"It was like a film, glass flying everywhere.
"It was a nightmare. I have never seen anything like that in my life."
He added: "They didn't need to throw glass - no one was retaliating."
Northamptonshire Police confirmed that one person was taken to hospital as a result of their injuries.
"We were called to the premises in College Street at 10.30pm on February 1 after a brawl erupted," said a force spokeswoman.
"One victim was glassed to the head and taken to hospital, another was hit on the head numerous times and another person was bottled."
A person working at the pub said three people "had a fight".
Witnesses or anyone with information about this incident are asked to contact Northamptonshire Police on 101, or call Crimestoppers in confidence on 0800 555111.