SPOKANE, Wash. (AP) _ Their faces stare out from posters mounted to the sides of buses, lumbering along the same route where many of them walked as prostitutes.

Their eyes reflect fear, nervousness or anger at being arrested and photographed in the middle of the night. They are all the victims of a serial killer who has eluded an intense yearlong homicide investigation.

So far, there have been no arrests and no named suspects.

``Help us find our killer,'' the Spokane Transit Authority posters implore over enlarged police mug shots of the slain women.

The joint Spokane County-City homicide task force has confirmed nine victims of a killer or killers since last November here and in Tacoma, 300 miles to the west. As many as 17 other deaths since 1990 are also being investigated for possible links.

The confirmed victims were all prostitutes and drug users. Each had been shot and dumped in remote locations sometimes months after their disappearances.

``We're making progress,'' said the task force co-commander, Spokane Sheriff's Capt. Doug Silver. He admits to feeling frustrated that many of the victims died after the task force was formed, ``but I do believe we will catch this person.''

The task force has doubled in size from four detectives to eight and investigators have chased and cleared about half of the 3,000 tips they've received in the past year.

Lynn Everson, a Spokane Regional Health District AIDS outreach worker known by prostitutes as ``The Condom Lady,'' said the task force moved quickly to establish a rapport with street women who are the killer's likely targets.

Two homicide detectives frequently walk the streets, talking to prostitutes to glean information and have developed a ``real trusting relationship'' that has benefited the investigation, she said.

In turn, social workers have given investigators a list of ``bad tricks'' reported by prostitutes _ now at least three pages long with descriptions of customers and more than 100 vehicles.

But there has been criticism of the investigation.

Mark Sterk, who will lead the task force when he takes over as Spokane County sheriff in January, immediately called for changes in the way the task force is run after his election.

``One thing I have heard is it has been kind of a shotgun approach. We're going to narrow it down a bit,'' Sterk, a Republican state representative and sheriff's deputy, said in a recent interview.

Sterk said he wants detectives to concentrate on finding potential links between the victims and their killer, whose name likely is in police arrest records.

``I'm not sure if he's from Spokane, but I am convinced we have had contact with him,'' Sterk said. ``Either the sheriff's office, Washington State Patrol or Spokane Police have had contact with this guy and he is in our database.''

So far, the task force's refusal to publicly release a profile of the killer's criminal psyche has angered some residents in a city of some 180,000.

``We don't want to rule anybody out,'' said Spokane Police Capt. Steve Braun. Producing a psychological profile could make the list of potential suspects too narrow, Braun said.

``It's one of many tools,'' Silver concurred, ``not the total answer.''

Not everyone is disenchanted with the job the task force has done.

``I admire the members of the task force and feel they have a horrendous job to do,'' said Kathy Lloyd, the sister of Shawn McClenahan, whose body was found Dec. 26, 1997.

``They've always taken the time to speak with me. And I feel that communication is crucial in this situation.''

Among potential victims, however, there is growing frustration.

``They ain't doing such a great job, are they?'' asked a young prostitute working a street just off Sprague Avenue on a recent Friday.

Dressed in blue overalls with a ``Tweety Bird'' cartoon character on the front, she declined to give her name as she eyed passing cars.

``Gotta go. Gotta make some money,'' she said, climbing into a late model silver Honda.