A South Carolina man who was convicted of killing seven people earlier this year has now confessed that he murdered more, reports said.
Todd Kohlhepp, 46, was initially arrested after police searching for a missing couple found a woman, Kala Brown, chained like a dog inside of a container on his property.
Brown told investigators that Kohlhepp had shot her boyfriend, 32-year-old David Carter, and kept her chained for two months.
Kohlhepp pleaded guilty in May to seven counts of murder for killings that took place over more than a decade, reports said.
Now, Kohlhepp has reportedly confessed to more killings in an eight page letter to the Herald-Journal of Spartanburg.
Kohlhepp wrote that he told investigators and informed the FBI, but he said "it was blown off." He also wrote, "At this point, I really don't see reason to give numbers or locations."
At the time of Kohlhepp's sentencing, his attorney told the court there were no other victims.
But in his letter, Kohlhepp wrote that his murder trail, "leaves the state and leaves the country," the Herald-Journal of Spartanburg reported.
Kohlhepp is already sentenced to life in prison.
Don Wood, chief division counsel with the FBI's Columbia office, reportedly said the agency has a pending investigation, CBS News reported.
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