Serial Killer Israel Keyes "broke his own rule," the Anchorage police said on Monday, losing control of his methodical, painstaking effort to keep his murders a secret.

Keyes committed suicide on Dec. 2 in a jail cell by slitting his wrists and strangling himself with a rolled-up bedsheet. But before he did he confessed to killing at least eight people. He told police that he studied ruthless murderers like Ted Bundy, and learned how to maintain control covering the bloody path he created.

But when Keyes, 34, saw teenage barista Samantha Koenig on Feb. 1 in Anchorage, he couldn't help himself, Keyes told police. He dragged her into his car, raped her and strangled her. That was the event that ultimately led to his capture and arrest.

"In prior cases, he had enough self-control to walk away from it, to not commit the kidnapping, to not commit the abduction and with Samantha he didn't," Anchorage homicide Det. Monique Doll said Monday. "He broke his own rule. He had drawn his line in the sand and he couldn't help himself, he said. He took her anyway."

Now that Keyes has killed himself, too, additional information is emerging, including bloody, illegible notes found in his cell. They've been sent to an FBI lab for analysis.

The serial killer's arrest on March 12 was the end to a long, brutal killing spree, which involved burying murder kits of weapons, cash and tools to dispose of bodies. Since Keyes' arrest in March he had been giving police more of the gruesome details of the murders.

After 40 hours of interviews with police in which he admitted to torturing animals as a child, the police have been putting together the puzzle pieces of the vicious crimes. They believe Keyes killed between 8 and 12 people, including Koenig, but only three victims have been identified.

Keyes had two major rules that he felt would keep him from being found out. 1) Stay away from your own home. 2) Don't use your own vehicle. When he abducted Koenig, he broke both of those rules.

"Mr. Keyes told us that he was deciding as he walked up the coffee kiosk that if the person working inside did not have a vehicle he was only going to rob the [place] and walk away because he did not want to transport his victim in his vehicle," Doll said.

"He had researched and read other serial killers. He knew a lot about Ted Bundy," Doll said. "He was very careful to say that he had not patterned himself after any other serial killers, that his ideas were his own. He was very clear about that distinction."