Six people were injured, including one critically, in a hail of gunfire early Saturday morning outside a Main Avenue bar where two men were arguing, according to the Renton Police Department.

Four of the six shooting victims were transported to the Harborview Medical Center in Seattle, including the critically injured person. One victim refused treatment and the sixth gunshot victim was taken to Harborview by friends.

Renton Police investigators found more than 30 shell casings in the roadway and sidewalk area in front of the bar.

A Renton Police officer heard loud arguing outside Pounders Bar in the 200 block of Main Avenue as he drove by at about 1:30 a.m.

When he looked back at the area, he heard the sounds of rapid-fire gunshots, said Renton Police Commander Paul Cline.

A man standing in the middle of Main was exchanging gunfire with a second man standing with a crowd of people on the sidewalk, according to Cline.

The man in the street fled east.

Other officers arrived within a minute, finding several people had been hit by gunfire, according to Cline. They secured the scene and aided the injured.

The officer who initially responded tracked the fleeing suspect with a police K9 to the Cedar River, just east of Interstate 405. The 27-year-old Des Moines man was arrested and booked into the Renton jail for investigation of felony assault.

A second suspect, also a 27-year-old Des Moines man, was arrested a short time later at the scene and was booked into jail for investigation of felony assault.

The preliminary investigation determined that the subjects began arguing in the bar and then went outside, where the argument continued and then escalated into gunfire, according to Cline. One handgun was recovered near where the shootings occurred.

Pounders has been the scene of at least one other shooting.

A 19-year-old man was shot and killed and another man wounded in a shooting outside the bar at about 2 a.m. on Nov. 5, 2006. William Adam Gray was charged with second-degree murder in that case. He was also charged with first-degree assault.

Gray was on Renton’s Most Wanted list. He was arrested last January in Federal Way by a fugitive task force. The Renton Police Department had been aggressively pursuing Gray, working with federal authorities and using social-networking sites, such as MySpace, to find him.