Police responded to the scene, in the 2900 block of 1st Avenue South, at about 2 a.m. after receiving 911 calls about a fight disturbance and gunfire.
When officers arrived, they found a highly chaotic scene with an uncooperative crowd who would provide little help or information, said Detective Jeff Kappel of the Seattle police.
Police and medics identified three victims. The most seriously injured suffered a gunshot wound to the abdomen. He was rushed to Harborview Medical Center with life-threatening injuries.
The two other victims sustained cuts and bruises to the head, but no gunshot wounds. One of them was taken to Harborview with non-life-threatening injuries. The other was treated and released at the scene. The cause of their injuries is unclear.
A preliminary investigation found that a brawl broke out as a crowd of people left the nearby Republiq nightclub and walked to their cars at closing time. The fighting escalated into gunfire.
The victims and others in the crowd refused to provide much information, and no suspects were arrested. No information about the suspects is currently available, police said.
The investigation continues.