A Marine and Vietnam veteran who was found in a shallow grave in a wooded area of Pomona Park, Florida, in December 1980, after being "violently murdered" has been identified, the sheriff’s department confirmed. 

William Irving Monroe III was shot, had blunt force trauma to his chest, and a hairline fracture on the base of his skull, Putnam County Sheriff Gator DeLoach said in a Friday press conference. 

Monroe had been previously known as John Doe #36 and was thought to have been a migrant worker prior to his identification. 

Last June, DeLoach said an identification wasn’t looking likely due to the "degradation of biological samples that we had. However, Othram labs was continuing to build a workable DNA sample and after a significant amount of work on their part they were able to get a viable sample collected from biologicals we had in evidence." 

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By September, investigators were looking into the genealogy of possible family members related to Monroe, including a potential brother and sister. By January, officials said they had possibly linked the remains to Monroe, "which is promising, because there’s no records of Mr. Monroe after 1979."

DeLoach said after investigators called Monroe’s brother, they realized he was "not a migrant worker as we’d once thought, but a person who has ties to Putnam County, specifically Pomona Park."

Monroe’s ex-wife raised their two sons there, including his son, Michael, who was only 8 years old when his father disappeared, and attended Friday's news conference. Monroe’s other son, Chris, died in a car crash in 1994. 

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DeLoach said for years Monroe’s family thought he had possibly been murdered in the Virgin Islands and "we now know unequivocally that is not the case, and though this may be just a piece of the puzzle, it now gives them the peace to know that we have identified their brother who will be properly memorialized." 

Monroe’s father had hired a private investigator when he first went missing, DeLoach said, but since Monroe bounced around from state to state before his murder, they had no leads for a missing persons' investigation. 

Investigators are now turning their attention toward finding a suspect. 

Monroe was last seen at a convenience store in 1980 and a driver for a labor camp said he had picked up a person matching the description of Monroe’s remains around that time. 

"I wanted to get our victim identified because I know every victim has a family," Capt. Chris Stallings, with the sheriff’s department, told WJXX-TV. 

Monroe's brother Richard Monroe told the station that William had PTSD from Vietnam and stopped contacting the family in 1980. 

His son Michael told WJXX that his father was his "hero."

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"I went everywhere with him, so when he was gone, it took a lot out of me," he said. "I wondered about it my whole life. Just to know he was found and I wasn't abandoned as a kid... it is overwhelming, I don't know how else to say it. It's shocking."