A man charged over the death of an Alaska coffee bar worker has been found dead in his jail cell.
Israel Keyes died of an apparent suicide, authorities said on Sunday, without giving further details.
He was facing a possible death penalty for the murder of 18-year-old Samantha Koenig, who was abducted from her kiosk in Anchorage last February.
Investigators said Keyes confessed to her murder, but also to killing Bill and Lorraine Currier from Essex, Vermont.
They went missing in June 2011. Their bodies were never found.
Keyes also indicated he killed four other people in Washington state and one person in New York state, but did not give the victims' names.
Ms Koenig's disappearance in the depths of winter gripped Anchorage for weeks, until her body was recovered on April 2 from an ice-covered lake north of the Alaskan city.
CCTV pictures had showed an apparently armed man in a hooded sweatshirt leading her away from her coffee stand.
Prosecutors say Ms Koenig likely died just a day later, but Keyes then used her phone to send text messages to conceal the abduction, and to later demand a ransom.
He was finally arrested in Texas after using her debit card.
The FBI said there may be victims in other states, besides the four indicated by Keyes.
The 34-year-old was a self-employed carpenter and Army veteran who had been stationed at Fort Lewis in Washington state.
He moved to Anchorage in 2007 but also owned a house and property in Constable in New York state.