SCOTTSDALE, AZ — He is a man whose name has been prominent on America's Most Wanted list for 20 years. To this day, police have no clues as to where accused killer Robert Fisher may be, if he is even still alive.
"I would say it's been long enough. He needs, he needs to come in," said Scottsdale Police Detective John Heinzelman, who heads up the investigation surrounding the search for Robert Fisher.
Despite the lack of clues, investigators have not given up on their mission to find Fisher. Fisher is accused of murdering his whole family before disappearing in 2001.
FULL COVERAGE: Is Robert Fisher dead or alive 20 years after Scottsdale killings, house fire?
Those who knew the couple say they were having marital problems, and Fisher may have lost control after learning his wife Mary Fisher planned to divorce him. Police say Fisher slashed the throats of his wife and two children, Bobby and Brittany, before rigging up his home's natural gas line to explode in a house fire before disappearing.
Police believed the fire may have been an effort to conceal the horrific crime and delay police as he went on the run.
The last clue Fisher left behind was Mary's car, dumped in the Tonto National Forest near Young, Arizona. Police say the family dog was found alive by the car. There was no sign of Robert Fisher.
Despite a massive search in the area, Fisher has remained missing to this day. Police said they still get tips in this case and look into every single one of them.
If alive, police say Fisher looks different from the original photos of him depicted in family photos and home videos.
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"You have to remember everybody is 20 years older. So Robert Fisher will turn 60 in April. That is the first thing," said Detective Heinzelman.
"We're not looking for a 40-year-old person anymore. We're looking for a 60-year-old person. Now, maybe his height won't change, but his weight certainly could change, his hair could change, his facial features," added Heinzelman.
The FBI used special aging software to recreate multiple different looks Fisher could have adopted as he grew older.
Police said despite his outward appearance, Fisher was known to walk with an "exaggerated posture" due to back problems.
The case had also garnered attention from groups dedicated to "cold cases." A former Florida policewoman had taken it upon herself to purchase billboards and make T-shirts highlighting all of the age-progression photos put out by the FBI depicting Robert Fisher.
"I think it's just a horrible case and then to be on the 10 most wanted list, everybody should know who these people are," said Christine Burke who founded HelpSolveTheCase.com.
Part of the lure she admitted was the $100,000 reward in the case that would help her organization take on more "cold case" investigations they could publicize and promote.
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Although his face and body may have changed, police said what was inside Robert Fisher, the dark mind of an accused killer, still remains the same.
"This case has turned into...that's the case you want to solve," said Detective Heinzelman. "It is the biggest case we have in Scottsdale that is still active."