Nov. 13, 2013  -- A New Jersey woman who vanished in 2009 may have been the victim of an Alaskan serial killer who traveled the country to find random victims to murder for pleasure, the FBI said today.

Before Israel Keyes committed suicide in prison on Dec. 1, 2012, he led investigators to believe he had killed at least 11 people. Three of the victims have been identified and FBI officials believe Hackensack, N.J., resident Debra Feldman may be the fourth.

Keyes admitted to investigators that he abducted a female victim on April 9, 2009 from a state on the East Coast and transported her across multiple state lines into New York, the FBI said in a statement today. Keyes said he murdered the woman and buried her in the Tupper Lake area of upstate New York.

Today, the FBI said they believe that woman may be Feldman, a 48-year-old woman who was last seen on April 8, 2009.

"To date, Ms. Feldman's body has not been recovered," the FBI said. "Investigators are requesting that anyone who knew Ms. Feldman and may have information about her activities around the time of her disappearance contact the Hackensack Police Department or call 1-800-Call-FBI and follow the prompts for the Israel Keyes."

The FBI did not immediately respond to a request for more information on how investigators connected Keyes to Feldman.

Serial Killer Israel Keyes' Suicide Letter Is Creepy Ode to Murder

The arrest of Keyes, 34, on March 12, 2012 for the murder of Alaskan barista Samantha Koenig ended more than a decade of traveling around the country to find victims to kill or to prepare for future crimes by burying what he called murder kits of weapons, cash and tools to dispose of bodies.

Since March of 2012, he had been slowly telling police about his hidden life and how he operated. But the tale abruptly ended when Keyes committed suicide.

Since then, investigators have been trying to fill in the details of his vicious life. The FBI said that Keyes discussed "seven or eight other victims" in addition to the three, including Koenig, that have been definitively tied to him so far.

The FBI previously said they believed Keyes killed and buried a victim in upstate New York in April 2009, which now appears to be Feldman. He also told them about killing a couple in Washington state sometime between July 2001 and 2005. He also told investigators about another victim in the Washington area and possibly others in surrounding states, the FBI said.

Investigators believe that Keyes did not know any of his victims before their abductions and said he looked for victims in places like parks, cemeteries, campgrounds and boating areas. He also admitted to frequenting prostitutes during his travels, the FBI said, but it is unknown if he met any of his victims that way.

He indicated that the victims were male and female and ranging in age from their late teens to the elderly.

Serial Killer Israel Keyes 'Broke His Own Rule,' Lost Control

In August, the FBI released an online package of information related to Keyes that includes hours of interrogation videos, photos and an interactive timeline that traces Keyes' known whereabouts from 1997-2012.

The FBI asked that if the videos or map trigger any memories or if people have any information regarding Keyes, please contact your local FBI office, call 1-800-CALL-FBI, or submit an online tip.