NEWPORT — Maine State Police are searching for new evidence in a 37-year-old unsolved murder investigation. “This is a continuing investigation. It’s been underway since ’77, when the body of an Ellen Choate was found in a shallow grave in Newport, and we have made the decision to revisit that area today looking for additional evidence that might be related to the case,” said Stephen McCausland, spokesman for the Maine Department of Public Safety. No person has been charged in the killing. McCausland would not say what caused police to return to the scene. “We have six investigators up there, and they will be up there for the rest of the afternoon,” he said. Police have been investigating the crime since the discovery Choate’s remains in wooded area off Old County Road in 1977. Law enforcement determined she had died about two years earlier from a gunshot wound to the head. Choate, a Pennsylvania resident, was one her way to Bangor to begin a teaching job at the time of her disappearance. This story will be updated.