Two men were treated in hospital after an incident in Huddersfield town centre in the early hours of Sunday.
Police are still trying to piece together the series of events which occurred in the Byram Street area of the town centre at around 4.45am.
St Peter’s Gardens was sealed off on Sunday morning as police investigated.
But they are appealing for witnesses to come forward with any information they have relating to the incident.
Det Insp Andy Parr, from Huddersfield CID said: “It’s early in our investigation, but we know that two people required hospital treatment in relation to this incident.
“One man presented at hospital with a stab wound. It is a superficial wound but it’s unclear what happened.
“At around the same time, two males were found in St Peter’s Gardens near the bottom side of the church off Byram Street.
“One of them was unconscious and he is currently in hospital, we hope to be able to speak to him later.
“The other had a cut to his hand, it was a minor cut.
“We are tenuously linking this incident with the male who presented at hospital.”
The males involved are 26, 36 and 20.
The incident took place just hours after thousands of people left the town after the successful Festival of Light.
St Peter’s Gardens, next to Huddersfield Parish Church, where the incident took place, had been used as a market.
Anyone with information about the incident is asked to contact Huddersfield CID on 101.
In unrelated investigations, police would like to speak to the people pictured in the image gallery below. The people pictured in the images may be witnesses as well as suspects. If you recognise anyone, contact police on 101 quoting the reference number on the image caption.