MEMPHIS, Tenn. — Seven people have pleaded guilty to smuggling oxycodone pills from Nevada to Tennessee through the U.S. mail.

The U.S. attorney’s office in Memphis said Thursday that an organization led by Courtney M. Jones managed the illegal delivery of oxycodone from Las Vegas to western Tennessee for sale in the region.

Prosecutors say the U.S. Postal Inspection Service started an investigation into packages suspected of containing the opioid pain pills in May 2013. Inspectors identified phone numbers, surveillance images and other information connecting two defendants to packages sent through Express Mail.

An undercover inspector delivered to Jones’ apartment an Express Mail package. Investigators found about 700 oxycodone pills and more than $53,000 in cash.

Jones and the six others who pleaded guilty to distributing oxycodone face sentencing early next year.