The South Carolina prison system says 10 inmates were mistakenly released early from prison over the last two years.
The State newspaper reports that four of the inmates have yet to be recaptured.
South Carolina Department of Corrections spokeswoman Chrysti Shain told the newspaper that the inmates were mistakenly released because of a miscalculation. Inmates are supposed to be eligible for release only after serving 85 percent of their sentences.
The error was discovered in February while the department was reviewing records for parole.
Shain said most of the inmates were serving time for drug sentences. State Sen. Katrina Shealy, who spoke with corrections officials, said other crimes included burglary and domestic violence.