More suspects have been charged in connection with what federal prosecutors say was a sex trafficking ring that forced women into prostitution and traded them like slaves between cities in Georgia, Florida and the Carolinas.

An indictment filed Thursday in U.S. District Court in Savannah added 13 new defendants to the case, which prosecutors said included some men who paid for sex. A total of 25 suspects have been charged since January.

Prosecutors say since 2008 a network of pimps lured dozens of women to the U.S. from Mexico and Central America and forced them into prostitution. They say some women were forced to have sex up to 30 times a day.

The new indictment says some women worked as prostitutes because pimps threatened to harm their children in Mexico.

Tags: Savannah, sex trafficking, human sex trafficking