Police are appealing for witnesses and mobile phone footage of a disturbance in a Bristol nightclub after a 37-year-old man died having been stabbed multiple times.
A murder investigation was launched when the man, who police named as Jamel Powell, died two hours after being attacked in the Blue Mountain Club in the Stokes Croft area of the city early on Saturday morning.
On Sunday, Avon and Somerset Police said a post-mortem examination found Mr Powell, who was taken to hospital following the incident at 3am, died from multiple stab wounds.
A 39-year-old man was arrested at the scene in connection with the inquiry and a second man, aged 55, was arrested later.
Both men remain in police custody.
Detective Superintendent Carolyn Belafonte said the force would like to speak to anyone who witnessed the incident or who may have filmed any part of it on their mobile phone.
"If you have footage of the disturbance, or have seen it posted on social media, please get in touch," she said.
"Any information, no matter how insignificant you think it might be, could prove to be vital."
Detective Superintendent Belafonte said the club remained closed while crime scene investigators continued to examine it for evidence.
She added: "A full investigation is being carried out into the circumstances of this tragic incident in which a man has lost his life.
"His next of kin have been informed and are being supported by specially trained liaison officers.
"Our thoughts are with them at what is undoubtedly a difficult time."
She said the force was "aware this will have an impact on the wider community" and had increased patrols in the area to provide reassurance.
Anyone who witnessed the incident or who has footage of it is asked to call 101 quoting reference 5217295746 or to call Crimestoppers confidentially on 0800 555 111.