The FBI on Monday released an updated timeline detailing the possible whereabouts of confessed serial killer Israel Keyes between 1997 and 2012, when the agency believes he may have killed as many as 11 people. The FBI said that the new timeline is the result of investigation and analysis of interviews conducted with Keyes prior to his death in December of 2012, when he killed himself in his Anchorage jail cell while awaiting trial for the kidnapping and murder of 18-year-old barista Samantha Koenig in February of that year.

Keyes frequented remote areas like campgrounds, trailheads and cemeteries to pick victims, according to the FBI. The specifics of his murders are largely unknown, and the FBI hopest that by elaborating on Keyes' whereabouts and the nature of his crimes, anyone with information might come forward to provide details on who Keyes' victims may have been.

"In a series of interviews with law enforcement, Keyes described significant planning and preparation for his murders, reflecting a meticulous and organized approach to his crimes," the FBI wrote in a release accompanying the timeline.

"It's a more comprehensive timeline," Anchorage FBI Special Agent Eric Gonzalez said of the updated breakdown of Keyes' whereabouts. "It's based on investigations and on speaking with Keyes. It's the best timeline that we have -- we're really just opening it up and putting it all out there at this point."

Anchorage police have said that they believe Koenig was Keyes' only Alaska victim, though he described to them in chilling detail other instances when he hid a cache of body-disposal equipment in Eagle River and considered shooting a couple at a parking lot at Anchorage's popular Point Woronzof.

Keyes moved to Anchorage in 2007, where he worked as a general contractor, performing various private construction jobs around the area. He lived with his girlfriend and daughter at a home in the Turnagain neighborhood of west Anchorage.

Keyes confessed to the killing of Koenig after his arrest in Texas in March of 2012. Authorities said that Keyes kidnapped her from her workplace, a coffee stand on busy Tudor Road in Anchorage, on Feb. 1, 2012 and killed her. Weeks later, he dismembered her body and dumped it in Matanuska Lake. Koenig's body was recovered following Keyes' arrest.

Keyes was arrested as authorities tracked a paper trail tied to a debit card used by Koenig that Koenig's father, James Koenig, had deposited ransom money on to in hopes of using the withdrawals to track Keyes's whereabouts. After traveling through the southwestern U.S., authorities finally caught up to Keyes in Lufkin, Texas.

After his arrest, Keyes expressed his hopes for a speedy trial and his desire to be assigned the death penalty. In exchange, he shared information with investigators, though much of it was cryptic, withholding details like victims' names or exact locations of bodies or murders. In addition to Koenig, the only other victims of Keyes to be identified were Bill and Lorraine Currier, a Vermont couple who Keyes confessed to killing in June 2011. In all, the FBI believes Keyes may have had as many as 11 victims, thanks to a statement from Keyes that he had killed "less than 12" people.

The FBI's updated timeline provides further details on where authorities believe some of those murders took place. They include:

 A murder between July and October 2001, when Keyes was residing in Neah Bay, Wash.

 Keyes admitted killing two people in Washington state between July of 2001 and 2005. Keyes refused to tell law enforcement if the couple was married or what their relationship to one another was, the FBI said. It is unknown if the victims were residents of Washington, tourists, or residents he abducted from a nearby state and transported to Washington. Keyes alluded to the fact these victims were buried in a location near a valley.

 Two murders, independent of each other, in the summer or autumn of 2005 or 2006. In these cases, Keyes said that he disposed of the bodies from his boat, based in Washington. Keyes stated at least one of the bodies was disposed of in Crescent Lake in Washington, and he used anchors to submerge the body, the FBI said. Keyes reported the body was submerged in more than 100 feet of water.

 Keyes admitted to kidnapping a female victim from somewhere on the East Coast in April of 2009 before killing her and burying her in upstate New York. The FBI said that they do not believe the body is buried at a property that Keyes owned in Constable, N.Y.

 Bill and Lorraine Currier were murdered in Essex, Vt. on June 8, 2011.

 Samantha Koenig was murdered in Anchorage in February 2012.

Keyes said that at least one other murder was ruled accidental by authorities after he moved the body to a location and positioned it in such a way that it would be seen as an accident. This was reportedly the only other murder besides Koenig's in which a body was recovered.

Most details of the murders are scattered, like this other example Keyes provided to authorities about a woman he said he kidnapped and killed: "The female is described as having pale skin, possibly having a wealthy grandmother, and driving an older car at the time of her abduction."

Keyes took several other trips, during which the FBI said it believes he may have committed other crimes. Keyes also admitted to burying various caches of weapons, money and body-disposal equipment around the U.S., and authorities recovered two of those caches. But kidnapping and murder weren't Keyes' only crimes.

"Keyes admitted responsibility for robbing several banks during this time frame, two of which investigators have corroborated," the FBI wrote in the release. "Keyes used the proceeds from his bank robberies to pay for his travel, along with money he made as a general contractor."

The release added that Keyes admitted to dozens of burglaries, and to using arson as a means of concealing a murder.

Keyes also took numerous international trips, where authorities believe it is possible he committed further crimes.

To see the full timeline, click here. Anyone who might have information in the Keyes case is asked to call 1-800-CALL-FBI.