Auburn Police Cmdr. Mike Hirman said dozens of people were leaving the Sports Page Tavern in Auburn at closing time around 2 a.m. when two groups began fighting in the parking lot.
Several people pulled handguns and fired shots, and three men were killed. A fourth man suffered multiple gunshot wounds and was in stable condition at Harborview Medical Center in Seattle, Hirman said late Sunday. The ages of the four run between 21 and 32.
Home video recorded at the scene shows people screaming and running from the area as at least eight gunshots are fired.
Problems between two groups, one celebrating a birthday, started inside the tavern when two women had a disagreement.
"The dispute started between two women when one of them danced with a man," Hirman said in a statement late Sunday night.
Witnesses identified the three men killed as 24-year-old Lorenzo Duncan, 26-year-old Nicholas Lindsay and Antuan Greer, who also is in his 20s.
Hirman said some of the victims and suspects knew each other.
Relatives describe the friends as men who loved their families and did not run with gangs.
"We grew up with each other," said one friend of Greer. "He wasn't even in that type of life for this to even happen to him. I loved that man."
Friends of Lindsay tell KOMO News that he leaves behind two children.
And friends of Duncan describe him as a polite young man who always dressed nicely.
"One of those gentleman you'd always want to have around," said one friend.
Investigators detained another man at the scene who had grabbed a gun and fired five shots at the shooter and surrounding crowd, prosecutors said. He is being held on $250,000 bail for investigation of reckless endangerment and being a convicted felon in possession of a gun.
Police have recovered several handguns. They believe several different firearms were used based on shell casings recovered from the scene.
Police in the neighboring suburbs of Federal Way and Kent stopped two vehicles that matched descriptions of cars leaving the scene of the shooting.
Those vehicles were seized, and their occupants were being questioned, said Hirman. The car stopped in Federal Way was riddled with bullets.