Investigators have found the skeletal remains of 10-year-old boy who vanished with his grandmother three years ago, and authorities said Monday they believe both were slain by an electrician who killed three people before committing suicide last month, according to Local 6 News.

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Officials said Monday that Joshua's remains were found in some woods in Cassadaga, Fla., over the weekend.

Douglas McClymont, (pictured, right) a man who performed electrical work in the house at one time, according to Volusia County Sheriff Ben Johnson.

In early May, McClymont shot a longtime acquaintance and kidnapped the man's wife before driving to North Carolina. In the town of Franklin, he shot to death a married couple, then McClymont kidnapped his estranged wife.

McClymont turned a handgun on himself after North Carolina authorities pursued him when he fled a traffic stop May 2.

Johnson said investigators interviewed McClymont shortly after the disappearances of Bryant and Martin. But McClymont told authorities he couldn't have done the crime because he was smoking crack with friends at the time, Johnson said.

On May 12, 2001, Martin, 77, and Bryant were reported missing from their home on West Seagate Drive. There were no signs of struggle at the home and no evidence was found during several searches of the home.

The missing boy's sister, Joanne Miller, told investigators that Martin and Bryant were home about 7 a.m. when her husband left work and she went to a charity event.

When Miller returned home around 11 a.m, she discovered her grandmother and brother missing, but Martin's car was still in the driveway.

Since then, investigators have checked out more than 1,000 tips, including several reported sightings of the pair but nothing has led to a break in the case.

In November, the pair were featured at the end of the show "Without A Trace" on Local 6 News in hopes of possibly generating some new leads.

The search continues for Martin.

Watch Local 6 News for more on this story.