The FOX 13 broadcaster reported, citing investigators, that the shooting happened at the Purple Haze club around 3 a.m. local time (08:00 GMT).
Police and fire engines have also been spotted at the scene. The area around the bar has been cordoned off.
The reason for the incident is still unknown.
BREAKING: Police are gathered inside Purple Haze nightclub at Lt. George W. Lee/2nd Street in downtown Memphis, where a shooting was reported around 3:30 this morninrg. We’re told 5 people were hurt. 4 of them were shot. Conditions unknown. @WMCActionNews5 pic.twitter.com/SFFimP9FUs— Brandon Richard (@BrandonLRichard) September 10, 2018