By CBSBoston.com Staff

SPRINGFIELD (CBS) — A Springfield altar boy who was found dead almost 50 years ago was likely murdered by a priest he knew, the Hampden County District Attorney’s Office announced Monday. The suspect, Richard Lavigne, died on Friday.

Thirteen-year-old Danny Croteau was found in the Connecticut River in Chicopee on April 15, 1972. He was still dressed in his clothes from the previous school day. The medical examiner’s office ruled Danny was killed by blunt force trauma to the head.

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Lavigne was a Roman Catholic priest and friend of the Croteau family. He frequently spent time with Danny and his brothers without their parents.

The Hampden County DA says Danny Croteau (left) was likely murdered by Richard Lavigne (right) (Photo Via Hampden County DA, WBZ-TV)

Lavigne was a person of interest following Danny’s death after telling police inconsistent stories and being seen at the river bank on April 16, 1972. Danny’s brother also told investigators that Lavigne called on April 17, 1972, and said “we’re very sorry what happened to Danny.  He saw something behind the Circle he shouldn’t have seen.  It was an accident.”

The brother said Danny would come home sick to his stomach from alcohol after being with Lavigne.

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It was within the last year though, that investigators were able to gather enough evidence to prove Lavigne was the killer. A key breakthrough involved a series of interviews with Lavigne.

“Through all the interviews, Lavigne refused to affirmatively admit that he killed Danny Croteau. Lavigne at times was cagey and evasive, continuing his long-running attempts to mislead and distract investigators. However, he made several statements to indicate that he was the last person to see Danny Croteau alive, that he brought him to the riverbank on April 14, 1972, that he physically assaulted him there, and after leaving Danny there, in his words, and returning a short time later, that he saw Danny floating face down in the river,” said D.A. Anthony Gulluni.

In a recording of one of the interviews, Lavigne is heard saying, “I just remember being heartbroken when I saw his body going down the river knowing I was responsible for giving him a good shove you know?”

Lavigne said he didn’t try to rescue Danny or tell police or Danny’s family about his whereabouts.

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Decades after Danny’s death, Lavigne was convicted of child molestation.

CBSBoston.com Staff