This is the first in a multi-part series on Arizona's Most Wanted.

Future installments will air on 12 News at 10 on Friday nights and and be posted here.

Name: Robert Fisher

Age: 55

Description: 6-foot tall white male with light complexion, blue eyes, brown or gray hair, medium build and surgical scars on his lower back; known to chew tobacco heavily

READ: Scottsdale PD report on Robert Fisher

Last seen: 2001

Wanted for: The FBI believes Fisher slit his two children's throats while they were sleeping and shot his wife execution-style before blowing up the family's Scottsdale home in April 2001. The prior evening, his daughter had been inducted into the National Junior Honor Society at her school. Fisher's wife Mary was not at the ceremony, but Fisher was, and his behavior was odd, her teachers told Scottsdale police.

FBI Special Agent Robert Caldwell said he believes Fisher's wife Mary was preparing to leave him because she thought he was having an affair.

His SUV was found 10 days later in the Tonto National Forest along with the family dog. No trace of Fisher has been found since. An avid outsoorsman, the FBI believes Fisher was well equipped to survive in the wilderness. The Bureau also believes he has several weapons, including a high-powered rifle.

There is a $100,000 reward for information leading to Fisher's arrest. If you have information about him, contact the FBI at 1-800-CALL-FBI (225-5324). The Phoenix Field Office's phone number is 623-466-1999.

PHOTOS: Time-progressed renderings of Robert Fisher