It happened around 2 a.m. MT inside the Basil Ultimate Pho and Fine Vietnamese Cuisine, located at 2770 32 Ave. N.E.
Police say three men in their 30s and 40s were found with gunshot wounds.
One man was declared dead at the scene, while two others were transported to a local hospital. Their conditions are unknown at this time.
A short time later, a fourth victim showed up at the same hospital suffering from a minor gunshot wound. Police believe her injuries were sustained during the same shooting.
Police say the shooting was not random and they are looking for suspects.
Officials won't say whether the shooting is gang related but investigators say they will draw from experiences from the 2009 New Year's Day triple murder at the Bolsa Restaurant.
Sanjeev Mann, Aaron Bendle and Keni Su'a were shot that day in the city's southeast.
The gun exchange was part of an escalating feud between rival gangs Fresh Off the Boat and FOB Killers. Four men have been found guilty for their roles in the shootings.