A Miller County school was on what is described as a “soft lockdown” Tuesday. Miller County R-III schools in Tuscumbia issued a press release saying they initiated the protocol following the discovery of a single round of ammunition in the school parking lot. The discovery came Tuesday morning and school officials say they don’t know when or how the ammunition got there. As a safety precaution, they called in the Miller County Sheriff’s office to provide additional security. No threats were found and the soft lockdown was lifted.