Kershaw County, South Carolina (WLTX) -- The sister of a Kershaw County man, whose body was found in a shallow grave, is asking for the public's help.

Kershaw County deputies say they've recovered the body of Adam Davis, who'd been reported missing at the end of last year.

On Wednesday afternoon, officers say they discovered Davis' remains in a shallow grave in Lee County. They went to that area after they got an anonymous tip via a letter. The letter included GPS coordinates.

Authorities now say they're classifying his death as a murder investigation.

Kershaw County Sheriff Jim Matthews says it's unusual to get a tip like that, but it's helpful because it brings closure to the family.

"He had a family that loved him very much. He had children of his own, so they don't have a daddy anymore," said Matthews.

Authorities are still looking for more information and Davis' sister, Heather Kelly, is asking those to speak up.

"Put yourself in our position. Think about what we are going through and do the right thing," she said.

Investigators sent their cadaver dog with deputies, who helped officers find the exact location of Davis' body. South Carolina Law Enforcement Division forensic investigators were called in to process the scene, and were able to confirm the man's identity definitively on Thursday.

His body had no visible wounds, Matthews said. The remains were not in bad condition, but he adds it's suspicious for the body to be buried.

The sheriff believes whoever did this knew that area and where to take the body to be buried.

Davis, who lived in Bethune, had been reported missing on December 29 th. While investigators initially thought he was missing, they later turned it into a recovery operation.

Sheriff Matthews said they will not be releasing the cause of death because it is part of the murder investigation.