Today they released CCTV images of 14 people who may have information on the shooting outside Nitetrax in the early hours of Monday, August 29.
A 42-year-old man was seriously injured in the incident outside the nightclub in Chapeltown Road.
Toyan Issac, 29, from Meanwood, has been charged with attempted murder and firearms offences in relation to the incident.
The case is currently going through the courts, but police investigations are also continuing.
Detective Chief Inspector Mark Swift, of West Yorkshire Police Homicide and Major Enquiry Team, said: “We have carried out comprehensive checks on CCTV at the venue and have identified these 14 people as potential witnesses.
“We want to stress that we are only interested in speaking to them as potential witnesses to this incident and not in relation to any other matters.
“This was a very serious incident where a man was injured as a result of the criminal use of firearms and we hope that anyone who can assist the investigation will come forward.”
Any of the people shown in the images or anyone who knows their identities is asked to contact the Homicide and Major Enquiry Team on 01924 821438.
Those with information can also call 101, quoting Operation Plainridge, or contact the independent charity Crimestoppers anonymously on 0800 555 111.