BOSTON (CBS) – There may be new evidence in the Molly Bish murder case.

The 16-year-old disappeared 14 years ago Friday, while working as a lifeguard at Comins pond in Warren.  Her remains were found three years later in a wooded area of Palmer.

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The new evidence, now in the hands of state police for testing, was found by a private investigator working for the Bish family.  Returning to where Molly’s remains were found in 2003, the investigator found a partially buried paper bag containing plaid boxer shorts and some pink clothing material — similar to the boxers and pink tank top that Bish was wearing the day she disappeared.

Her sister, Heather Bish, believes someone, possibly the killer, must have brought that bag to the scene after 2003 when Molly’s remains were found. She theorized that killers sometimes return to the scene of the crime.

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“Sometimes they do want to be caught,” she told WBZ NewsRadio 1030’s Mark Katic. “Sometimes they write letters and they put themselves forward, almost to sort of tease law enforcement.”

Heather Bish said that every new bit of evidence is emotionally charged for the family — giving them hope of finding Molly’s killer but also re-opening the old wounds of her death.

“Every time there is a suspect or a piece of information, there is this waiting and it churns your stomach,” she said.

“It’s been a roller coaster ride. We’ve had certainly lots of ups and downs. From the very beginning, the District Attorney John Conte has said we’re one piece of the puzzle away from solving this case. So my hope has always been: Shake the tree until that piece falls out.”

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