| ANCHORAGE, Alaska
ANCHORAGE, Alaska The search for victims of a dead U.S. serial killer is wrought with challenges - a wide expanse of territory where his crimes were committed, long stretches of vaguely accounted-for time and no single list of potential targets, officials say.
Israel Keyes, 34, who committed suicide in an Alaska jail on Sunday, had admitted to investigators that he killed an 18-year-old Anchorage cafe barista in February as well as a Vermont couple in 2011 and at least five other people in Washington and New York states.
Since the complete death toll remains unknown, investigators are trying to match missing-persons reports with a timeline, dating back to 2001, of Keyes' travels in Alaska, the lower 48 U.S. states and Canada.
"We know, based on our talks with him, eight. But it could be as high as 11," Eric Gonzalez, a special agent for the Federal Bureau of Investigation, said on Thursday, adding that he would not be surprised if the toll went even higher.
Keyes, a 34-year-old carpenter and Army veteran who spent time in Egypt's Sinai peninsula before the date he told investigators the killings began, died after he cut his wrist with a razor and choked himself with a piece of bedding.
From his arrest in March for the kidnapping and murder of Samantha Koenig until his death, Keyes dispensed bits of information about past crimes in interviews with authorities.
FBI experts were also trying to decipher possible messages that might have been left on pages of crumpled, bloody paper found in Keyes' jail cell, Gonzalez said.
Authorities found Koenig's dismembered body in April in an ice-covered Alaska lake, based on information gleaned from Keyes in interviews. But hers is the only body to have been recovered.
"Definitely I would think we, in the next year, will still be working on this case, trying to identify other victims," Gonzalez said.
Keyes also told investigators he put the bodies of Bill and Lorraine Currier in an abandoned Vermont house that was later demolished and that he disposed of bodies of four unnamed people in Washington state and one unnamed person in New York.
OREGON RAPE VICTIM SOUGHT
FBI agents in Oregon made a public plea on Friday for information about the person believed to have been the first victim of Keyes' violence - a girl he raped along the Deschutes River, but let live.
The rape happened between 1996 and 1998, and the victim was 14 to 18 years old at the time, the FBI said.
Keyes - who told investigators he selected some of his victims along hiking trails and at campgrounds - said he managed to separate the girl from her friends before attacking her.
"To date, authorities have not been able to find any relevant police reports that would fit this scenario and it is possible that the victim never reported it," the FBI said.
Keyes told investigators he planned to kill the girl after raping her but ultimately freed her. He also told them he began killing people in 2001, when he was living in Washington state and doing construction work for the Makah Tribal Council.
Keyes also said he was planning to commit more murders when he was arrested in March. He confessed to stashing kits of murder supplies - weapons, cash and tools to dispose of bodies - in various locations around the country.
Investigators found two of those kits, one in an Anchorage suburb and another in Blake Falls Reservoir in upstate New York, the FBI said.
Keyes told investigators all those he killed were adults who were strangers to him. Officials have said Koenig appears to have been his youngest murder victim and the only one from Alaska.
Complicating the search for victims, there is no national registry of missing adults as there is with children. Lists of missing adults are maintained by state law-enforcement agencies, officials in Alaska said.
In Alaska, where plane crashes, boat accidents in icy waters and other outdoor hazards are relatively common, some missing adults are presumed to have been victims of unfortunate mishaps, said Megan Peters, a spokeswoman for the Alaska State Troopers.
"Adults don't have to tell people where they are," Peters said. "They're adults and they have the right to privacy."
Nevertheless, Alaska officials treat all missing-persons cases with urgency, in part because of weather hazards. Unlike many other U.S. states, there is no 24-hour wait to start searches there, Peters said.
"When a missing person file is opened, it remains open until that person is found - dead or alive," she added.
(Additional reporting by Teresa Carson in Portland, Oregon; editing by Cynthia Johnston, desking by G Crosse)