What is a serial killer? Even the nation's leading experts don't agree. The most general definition is based on numbers and patterns: Two or more unrelated victims in distinctly separate incidents. The Northwest has a notorious history of these 'prototype' killers - among them are and the Green River Killer, who are synonymous with the term 'serial killer.' Yet other, less infamous killers have claimed scores of lives across the state.

• List Of Serial Killers In Minnesota
• Active Serial Killer Cases

Some have been convicted of only one or two murders, but are suspected of many more. Four remain only suspects, pending trial.

List Of Serial Killers In Minnesota

It's impossible to know if the list is comprehensive. There's no national database of serial killers. It's also true that some are better than others in hiding their morbid harvest. But it does show that killers often roam our state for years, exploiting holes in a law enforcement system that often fails to protect the missing or bring justice for the dead. Student/state employee, Seattle/Olympia A student in 1948, Gasser raped and strangled a 22-year-old carhop and dumped her body near the.

Years after his release from prison, he raped and strangled a 49-year-old woman and dumped her body in a ditch outside Olympia in 1982. Status: In prison in Washington. The Want Ad Killer Gas station manager Seattle/Minneapolis Suspected in dozens of sex-slayings spanning four decades and several Western states and provinces, Carignan is thought to have killed at least two women in Washington. He was convicted of two murders in Minnesota. He met some victims by placing newspaper help wanted ads.

A map found in his Minnesota home had at least 180 areas circled - including 18 in Washington - where some bodies have been found. Status: In prison in Minnesota.

City water department employee, Seattle Abducted, raped and strangled two women, then dumped their bodies near Stevens Pass. Canady later attacked two other women and was being held in King County Jail on rape, assault and kidnapping charges when he confessed to the murders, leading detectives to one body.

Status: In prison in Washington. Clark County parks employee, Vancouver Suspected of kidnapping, raping and strangling six women near Vancouver. Convicted of killing one and abducting, raping and attempting to kill two others, after serving seven years in a state mental hospital.

Status: In prison in Washington. Navy enlistee, Renton Confessed to four sex-slayings, including the murders of two 6-year-old boys and two teenage girls. All victims stabbed, strangled or both, then dumped in wooded areas near a Renton trailer park where he lived with his parents. Status: In prison in Washington. Ted Bundy Law student, Tacoma One of the most infamous serial killers of modern time, the former Tacoma man and law student is thought to have killed at least 36 young women and girls in Washington, Oregon, California, Utah, Colorado and Florida.

Status: Executed in Florida in 1989. Part-time church janitor, Lynnwood Attacked at least four women over 33-year span, killing two. Crimes include a 1966 robbery/kidnapping in Albuquerque, N.M.; a 1974 bludgeoning murder in Seattle; and the1998 fatal stabbing of one woman and sexual assault of another in a.

Status: Executed in Washington in 2001. Stable cleaner, Redmond Deemed a 'sexual psychopath' after attacking two Seattle women, he escaped, then raped and strangled two teenagers in West Seattle. He hung the body of one victim from a tree and hid the other in a field. He was arrested in Oregon after raping a 13-year-old girl. Status: In prison in Washington. The Phantom Sniper: Escaped mental patient, Burien Abducted, shot and buried a Burien housewife.

Suspected of killing as many as three women in Michigan, where he spent 15 years in mental hospitals. Texas authorities suspect him of killing at least one woman and sexually assaulting four others, and at one time questioned him about 16 sniper shootings on Texas freeways. Status: In prison in Washington. William Batten Car lot worker, Aberdeen Committed to state psychiatric hospital as a 'sexual psychopath' following child molestations in 1967.

Stabbed two teenage hitchhikers to death near Moclips in 1975. He remains a suspect in the 1969 disappearance of a woman he had dated.

Status: In prison in Washington. Robert Lee Yates Jr. Aluminum plant worker and helicopter pilot, Spokane Killed a string of prostitutes in Spokane and Pierce County since 1996. Admitted to 16 murders, convicted of 15. Typically would pick up prostitutes, shoot them and engage in post-mortem sex. Grew up on Whidbey Island and lived in several Washington cities.

Status: On death row in Washington. The Hillside Strangler: Security-alarm installer, Bellingham Strangled at least seven women and left their bodies on hillsides in Los Angeles. Also killed two students in Bellingham in 1979. He worked with an adopted 'cousin' convicted of nine similar murders in Los Angeles.

Status: In prison in Washington. Morris Frampton Sprinkler system installer, Seattle Beat to death a Seattle prostitute, then dumped her body near the South Park marina. Also convicted of assaulting two other Seattle prostitutes and acquitted of killing another. Status: In prison in Washington. Produce salesman, Spokane Suspected of killing up to 30 Northwest women, Bernson stabbed a 15-year-old girl to death and buried her in a shallow grave in Richland. Authorities in Oregon also charged him for the 1978 murder of a Umatilla teenager, whose body was found in 1985. Status: In prison in Washington.

Lewiston Valley Killer Identity unknown Believed responsible for five murders and disappearances in the Clarkston, Wash.- Lewiston, Idaho, area from 1979-82. Some victims were dismembered and dumped in a river. Two bodies have never been found. Victims include three young women, a girl and a man. Status: Investigators have a suspect, but have never made an arrest. The I-5 Killer: Bartender, Eugene/Portland, Ore. Suspect in at least 13 homicides, including three in Washington.

Best known for robbing, raping andkilling women in communities along Interstate 5 from Bellevue to Redding, Calif. Often wore a false beard and hooded sweat shirt during his attacks. Status: In prison in Oregon. Long-haul trucker, Spokane Convicted of raping and killing two teenagers in Spokane in 1983. He also killed two teenage female hitchhikers in Grant County in 1980. Avoided prosecution in those murders by later pleading guilty to the Spokane homicides. Status: In prison in Washington.

Coin Shop Killer: Transient, Deming Suspected in six murders in Washington state, including the killings of an elderly couple whose bodies have not been found. Robbed, raped and killed across several other Western states, including two suspected murders in Montana, two in California and one attempted murder in Utah. Sinclair often preyed on coin shops and their employees. Status: Died in jail in Alaska. The.22 Caliber Killer Identity unknown, Spokane.

The same killer is believed to be responsible for three slayings of women found dumped near the Spokane River in 1990. All of the victims were known prostitutes shot with the same.22 caliber gun. Investigators once looked at the crimes in relation to a string of prostitute killings in Spokane that Robert Lee Yates Jr. Later confessed to.

But the Army helicopter pilot was later ruled out as the murderer in these cases, as he was stationed in Germany at the time of the killings. First known murder 1990. Status: Unsolved. ( Note: This entry was added after the original publication of this list.) Army sergeant, Fort Lewis.

Shot and killed one prostitute, strangled and sliced the throat of another. Elton dumped his victims near Madigan Army Hospital in 1984. The Seattle native later pleaded guilty to the killings in military court to avoid a death sentence.

Status: In military prison in Kansas. Unemployed cook, Salem, Ore. Convicted of two counts of aggravated murder for the sex slayings of two young Salem women in separate attacks in the spring of 1984. Smith was also questioned in the 1983 unsolved murder of a 14-year-old girl in Idaho. Although not officially a suspect in any Washington murders, Green River investigators at one time looked at him in relation to serial killings in this state. Smith also has family ties to Pierce County.

Status: In prison in Oregon. Billy Ray Ballard Jr.

Truck driver, Plains, Mont. Confessed to killing a Seattle couple who disappeared while sightseeing in the Columbia River Gorge. Their bodies were recovered at different times, dumped 30 miles apart, in rural Grant County. Ballard's arrest for the abduction, rape and torture of two women in Wyoming months later helped investigators match his fingerprint to one left on the Washington couple's abandoned car. Status: In prison in Wyoming. Joe Kondro Laborer, mill worker, Longview Admits to raping and strangling two young girls in Southwest Washington - killings more than 11 years apart. Convicted of two other rapes, he also admits to abducting a teenage store clerk at knifepoint.

Suspect in dozens of disappearances, rapes and murders since 1982. Status: In prison in Washington. Unemployed, Tacoma Convicted of raping and killing two Tacoma women in separate attacks in early 1985.

Shaw dumped his victim's bodies in wooded areas of Pierce County. Status: In prison in Washington. Tattoo artist, Bremerton Convicted of raping and killing a 13-year-old girl - one of three hitchhikers he picked up, abducted and tortured. Yates also raped and tried to kill a 12-year-old boy and 13-year-old girl during the same attack. Later charged with killing a 35-year-old housemate in Oklahoma. Status: In undisclosed out-of-state prison.

Dismemberment Murders Identity unknown One killer could be responsible for three murders in which the victims' bodies were dismembered and dumped in remote areas inSnohomish County. One victim was a Bulgarian organized crime figure whose body was found in 1987, but wasn't identified for 10 years. Another was a Korean immigrant from Bothell with a record for prostitution. Her body was found with the remains of a third man, who has never been identified, in 1991. Status: Unsolved. John Bill Fletcher Jr. Convicted in 2001 of two stabbing murders of Yakima-area women in 1987.

He was a convicted rapist already serving more than 46 years for a similar 1987 sex attack when he confessed to the slayings. Status: In prison in Washington. The Index Killer Identity unknown One killer may be responsible for murders of two Seattle women whose bodies were dumped in the Index area in 1988. Both victims, known prostitutes and drug users, were stabbed. Three other women - two found dead nearby and a 14-year-old runaway last seen with one of the murder victims - may also be victims.

Status: Unsolved. Westley Allan Dodd Shipping clerk, Clark County Raped, tortured and killed three boysin Vancouver-Portland area. Caught after he tried to abduct a boy from a Camas movie theater. Admitted to molesting about 30 children. Status: Executed in Washington in 1993. Scott William Cox Long-haul trucker, Newberg, Ore. Stabbed one prostitute and strangled another in Portland.

Suspected in more than 20 other murders, including the 1988 homicide of Snohomish County transient Hazel Gelnett and the 1990 murder of Tia Hicks, a Seattle woman whose body was found in Montlake Terrace. Also suspected of raping and trying to kill a Seattle prostitute in May 1991. Status: In prison in Oregon. Happy Face Killer: Keith Jesperson Long-haul trucker, Yakima Valley/Portland Confessed to eight murders in five states. Jesperson typically raped, beat and strangled truck-stop prostitutes and transients, then dumped bodies along wooded roadsides. Sent taunting letters to media and authorities, signed with a 'happy face.' Caught after killing his girlfriend near Camas.

Status: In prison in Oregon. Eastside Serial Killer: Unemployed, Mercer Island Raped and killed three women he met in Eastside bars, leaving their bodies in particular poses. A small-time burglar/con-artist who pretended to be a cop, Russell made his living off women he met, through trickery and theft. Status: In prison in Washington.

The Box Car Killer: Robert 'Sidetrack' Silveria Railroad transient Claimed to have killed 28 drifters while riding box cars in seven states, mostly bludgeoning his victims with rocks and axes. Convicted of four murders - two in Oregon, one each in Kansas and Florida. Seven other murders also have been directly linked to him, though Silveria was never tried for these crimes. Member of the Freight Train Riders of America, a loose-knit gang of transients, Silveria frequently traveled to Washington from 1988 to 1996.

He was questioned about a transient's death in Klickitat County. Status: In prison in Oregon. Jack Owen Spillman III Laborer, East Wenatchee Raped, murdered and mutilated three females, including a 9-year-old girl, and a mother and her teenage daughter in a separate attack. Also charged with rape and robbery in Kent. Status: In prison in Washington.

Active Serial Killer Cases

Unemployed, Shoreline Separately killed two neighbor women and set fire to their Shoreline apartments in 1995. Also is suspected of shooting and killing a man in a passing car in 1996. ( Note: Details of the 1996 incident were incorrectly reported when this list was originally published.) Parker, an Arkansas fugitive who lived with his girlfriend in Shoreline, is suspected of a similar murder-arson that left one woman dead in Georgia in 1995. Status: In prison in Washington.

The Railroad Killer: Rafael Resendez Ramirez Day laborer, transient Robbed and killed at least eight people who lived near or spent time on railroad tracks around the Midwest and South in the late 1990s. Has not been named as a suspect in any Washington state crimes, but is known to have been in Seattle, the Tri-Cities and Spokane in 1996. Status: On death row in Texas. Dewayne Lee Harris Transient Killed three prostitutes and transient women in Seattle.

Typically would bind his victims' wrists and ankles with their shoelaces, gag them with their under clothes and strangle them, then leave bodies in vacant city lots. Status: In prison in Washington. John Eric Armstrong U.S. Navy, Bremerton/Detroit, Mich. Claims to have killed two women and a transsexual man in Seattlewhile stationed on the Bremerton-based USS Nimitz from 1993 to 1999, plus eight others worldwide.

Convicted of five Detroit-area prostitute murders. Police discount many of his claims. Status: In prison in Michigan. Awaiting trial Brian Keith Lord Carpenter, Kitsap County Suspected of the 1986 sex slaying of a Poulsbo teenage girl. At age 14, Lord shot and killed a family friendin California; and abducted his sister-in-law when he was 20.

His conviction and death sentence for the Washington murder was overturned, with retrial set for this year. Status: In Kitsap County Jail, awaiting trial. Green River Killer: Identity unknown Forty-nine murders are attributed to the Green River Killer, whose victims were prostitutes and runaways in the Puget Sound area. Ridgway, a South King County truck painter, is accused of killing Cynthia Hines, Opal Mills and Marcia Chapman in 1982 and Carol Christensen in 1983. Although all four deaths have been attributed to the killer, and Ridgway remains a suspect in other deaths, authorities are careful not to call him the Green River Killer. Status: Ridgway arrested in 2001, awaiting trial.

The Green River investigation continues. 'Cowboy' Braae Transient, Lacey Suspected of killing five women and assaulting others in Washington and Oregon. Braae faces trial in the slaying of Lori Jones, 44, whose body was found July 8, 2001, in her Lacey apartment. He is also charged in Yakima with shooting Marchelle Morgan, 50, of Yelm, also in July 2001. She survived.Braae is a suspect in the death of Velina Larson, 37, whose remains were found in Oregon in January 1998, and the disappearances of Deb VanLuven, 45, of Lacey, in 1997, and Susan Ault, 39, of Roseburg, in 2001.

Status: In prison in Idaho. Lee Boyd Malvo Student John A. Muhammad Mechanic, Tacoma/Bellingham Best known in connection with a seemingly random series of sniper shootings in the Washington, D.C.-area last fall, they are suspected of 13 slayings and five attempted killings in five states and the District of Columbia, including the fatal shooting of Keenya Cook in Tacoma in February 2002.

Status: Awaiting trial in Virginia.