(CNN) Police have found what they believe is the body of missing Alabama college student Aniah Blanchard, a prosecutor said.

Also Monday, authorities arrested a third man in connection with Blanchard's disappearance, according to Lee County District Attorney Brandon Hughes. The suspect, David Johnson Jr., of Montgomery, Alabama, was charged with hindering prosecution, said Hughes, who declined to elaborate.

Human remains were discovered in a wooded area of Macon County, Alabama, on Monday, according to Hughes. He told CNN that authorities have "good reason to believe" the remains are Blanchard's. Macon County is between Auburn and Montgomery.

An investigation by the Alabama Law Enforcement Agency and Auburn police is underway to determine the body's identity, according to an Auburn Police Department news release.

Blood was found in Blanchard's SUV

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