The discovery of human remains inside of a salt barn belonging to the Tennessee Department of Transportation sparked a homicide investigation on Wednesday, with officials wondering how on earth it got there. DOT workers’ discovery of the undamaged heart, which has since dehydrated to the size of a tennis ball, automatically triggered the case’s homicide status. Officials are currently speculating that the adult male heart may have been surgically removed due to its condition. Detectives are working to gather all the evidence before they rule out murder—though clues have reportedly been sparse, according to News Channel 5 Nashville. “Anytime we go on the scene where there’s a body or remains we treat it as a homicide, and then basically prove different,” said Humphreys County Sheriff Chris Davis. Authorities are currently working to get a DNA test performed on the heart, though it may take weeks for the results to come back. Some sources close to the case admit that it’s possible it may never be solved.