"This is a close-knit community," said police spokesman Jim Mattheis. "It's going to take somebody to put their fears aside and come forward."
When police arrived at the Trang Dai restaurant, the street was empty. They found the bodies of three men beside some booths and a woman's body near a rear door. Another man died later at a hospital.
Neighbors talked about gang activity at the bar, and translators were needed for many witnesses who spoke little or no English.
"We're speculating it was gang-related because of the type of shooting. It was not a robbery," Mattheis said. "They didn't say anything, didn't take anything."
One of the wounded, the bar's disc jockey, was hospitalized in critical condition and two, including Nguyen, were in satisfactory condition. The restaurant's owner and another person were treated for minor wounds and released.
Sixteen people were inside the bar-and-restaurant at 1:40 a.m., when the shootings happened. "I'm sure it had to be total pandemonium in there when the shooting erupted because there was nowhere for people to go," Mattheis said.
Police were investigating the burglary of a new car caught on a surveillance camera in an alley behind the restaurant.
Neighborhood residents said that a woman whose purse had been stolen learned the identity of the thief through a videotape and came into Trang Dai and threatened him with revenge last week. That woman's boyfriend allegedly has gang ties in the Seattle area,
A June 28 drive-by shooting at the restaurant also remains under investigation, Mattheis said. No one was hurt and no one was arrested.
He described it as "an establishment that we've had some interest in for criminal activities," but he would not elaborate.
Several months ago, a group of gang members streamed out from a passageway beside Trang Dai, chased a car to the corner and smashed one of the windows, said Pastor Alvis King Jr. of Restoration Christian Ministries, a storefront church near the karaoke bar.
One of the survivors of the attack that killed five people at the restaurant says he has no idea why anyone in the bar would be targeted.
Hoai Nguyen, 29, was at the Trang Dai cafe singing Vietnamese love songs with friends early Sunday when three men burst into the bar and started shooting. Ten people, including Nguyen, were hit by the spray of bullets. Four men and a woman were killed.
Nguyen, who was hospitalized in satisfactory condition with a shoulder injury, said in Monday's edition of The News Tribune of Tacoma that he thought people were still celebrating the Fourth of July when he mistook the sound of gunfire for firecrackers.
"He panicked. He saw another person fall. Then he just went ad sat down in the middle of the restaurant. He sat down in one place and tried to control his bleeding," Nguyen's translator told the paper.
Nguyen said he didn't see the shooters, and did not know why they would want to kill anyone at the bar in the heart of this city's Southeast Asian neighborhood.