Police tracked Irving down at the home he shared with his wife and granddaughter in Gorham, just west of Portland, where he was about to put his granddaughter to bed.
Irving was convicted in 1979 of kidnapping and raping three girls in Norfolk County, south of Boston, and fled after he was released awaiting sentencing.
According to the Boston Globe, Irving's was the longest-standing name on the Massachusetts State Police Most Wanted List.
When police arrived, Gregg Irving denied being Gary Alan Irving, but he was identified by a scar on his chest left by a childhood surgery.
"He was surprised to see law enforcement on his front door steps,” said Maine State Police Sergeant Robert Burke. “He just asked, ‘How did you find me?’ ”
Maine law enforcement said they are combing through open rape cases in Gorham and across Maine to see if any are similar to Irving's attacks.
He would drive around looking for teenage girls and young women to assault and hide in bushes, sometimes with a knife, Norfolk county prosecutor Louis Sabadini said. Sabadini handled Irving's original case.
"When they came by, he'd pounce on them, pull them into the woods and rape them," Sabadini said.
A victim helped lead to Irving's initial arrest by noticing a blue and white graduation tassel in his car, which police were able to track to Rockland High School.
Superior Court Judge Robert S. Prince, now deceased, allowed the then-18-year-old Irving to go home to get his affairs in order before the sentencing. He might have faced a 10 to 15 year sentence.
"If you let him out on bail now, it will just be an inducement to run," Sabadini recalled telling Prince. "And that's just what happened. He took off."
Neighbors said the Irvings may have lived in Gorham since the 1980s. They have a son and a daughter, and the granddaughter, and mostly kept to themselves.
The search for Irving, spearheaded by the Massachusetts police with help from local agencies, followed leads across New England, Georgia, Tennessee, Kentucky, Florida and Colorado.
Officials would not comment on how they ultimately found him.
Norfolk District Attorney Michael Morrissey said: "At the end of the day, good old-fashioned police work solved the problem."