Authorities have confirmed that a third suspect has been charged with murder in the ongoing investigation into the Holly Bobo case.

Knoxville ABC affiliate WATE reports that John Dylan Adams has now formally been charged with first degree murder in the perpetration of a felony, especially aggravated kidnapping, first degree murder in the perpetration of a felony, to wit: aggravated rape, and premeditated first degree murder. Adams had previously been charged with rape and tampering with evidence in the case, after an agent with the Tennessee Bureau of Investigation heard him confess that he had "disposed of item(s) he knew possessed evidentiary value relating to Holly Bobo."

At the time of his arrest in September of 2014, Adams was already being held on federal charges involving a previous indictment from Sept. 16, 2013, alleging that he knowingly "possessed, received, concealed, stored, bartered, sold and disposed of a stolen firearm” in July of 2013.

Bobo was a 20-year-old nursing student from Darden, Tenn. She went missing in April of 2011, and her remains were discovered more than three years later, on Sept. 7, 2014, in a wooded area of Decatur County, Tenn.  Adams' brother, Zachary Adams, has been charged with aggravated kidnapping and first-degree murder in Bobo’s death, and a third man, Jason Wayne Autry, has been indicted on charges of aggravated kidnapping and first-degree murder. Brothers Jeffrey and Mark Pearcy have also been charged with tampering with evidence and accessory after the fact.

30-year-old Shayne Austin was offered immunity in exchange for his testimony in the case, but the district attorney later rescinded that agreement, claiming that Austin had nullified the deal by not being truthful and fully cooperative. Austin committed suicide in February of 2015. In a bizarre twist in the case, Austin attended elementary school with Bobo's cousin, country singer and reality TV star Whitney Duncan.

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