Police are appealing to partygoers from Luton and Leighton Buzzard who may have witnessed a nightclub stabbing.
The attack happened at Liquid Envy, in Leicester, in the early hours of this morning.
It is believed that coaches of people from Luton and Leighton Buzzard attended the event called Urban Night.
Police are investigating a report of a stabbing at the nightclub on the outside terrace. The incident took place at 2.10am.
One man sustained puncture wounds to his chest and is in a critical condition at Leicester Royal Infirmary.
The second victim sustained a wound to his bottom and is in a stable condition.
Two men, aged 18 and 24, have been arrested on suspicion of GBH and remain in police custody.
If you witnessed the incident, please contact DS Gareth Goddard from Leicestershire Police on 101. You can also call Crimestoppers anonymously on 0800 555 111. Your personal details won’t be taken, information isn’t traced or recorded and you will not be required to go to court.