By CBSBoston.com Staff

BOSTON (CBS) – More than 20 years after Molly Bish disappeared from her lifeguard post in Warren, a person of interest has been named in her murder.

Police began interviewing Frank Sumner Sr. after receiving a tip in the case. Sumner died in 2016, but the search for information is not over.

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In an interview with WBZ, Molly’s sister, Heather Bish, said this new information might finally give her family the answers they have been searching for.

“I’m a teacher and I have been trying to find a murderer for 20 years and it’s been really hard,” Heather said. “I will be really grateful to be just a teacher again.”

Molly Bish and person of interest Francis Sumner (Photos from Getty Images and Worcester County District Attorney’s office)

Bish was 16 when she disappeared from her lifeguard post at Comins Pond in Warren on June 27, 2000. Her remains were found three years later in Palmer.

“I needed to know who took my sister and left her on the side of a mountain for a long time, that was important to me,” Heather said.

Heather said it was a recent tip that helped investigators identify Sumner as a person of interest.

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According to the Worcester County District Attorney, Sumner was a convicted sex offender and was well known to law enforcement in Central Massachusetts.

Heather is happy the case is progressing, but said she is scared to find out more.

Heather Bish (WBZ-TV)

“Knowing who did this to Molly has always been important to us and been our objective and our goal to get this person off the street, so of course we are grateful and relieved that that is possible but we are scared. We are scared to know what happened to Molly,” Heather said.

“Just reading about what he has done to other women and that potentiality of what he could have done to Molly is frightening and it makes sort of the nightmares become real so it’s bittersweet. It brings us back to that day.”

Anyone with information on Sumner or any additional information on the Molly Bish case is asked to call the district attorney’s anonymous tip line at 508-453-7575

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“I don’t know that we’ll know exactly what happened to Molly, but if we know the person who did it, that’s good enough for me,” Heather said.

CBSBoston.com Staff