Authorities in South Carolina have charged 21 juveniles for making "extremely serious" threats against local schools, the state's law enforcement division said.

The charges are part of a sprawling investigation into more than 60 threats targeting schools in 23 counties since a mass shooting on Sept. 4 in Georgia in which four people were killed at a high school.

Officials with the South Carolina Law Enforcement Division (SLED) say the agency is aware of over 60 threats targeting schools throughout 23 counties.

The South Carolina Law Enforcement Division (SLED) is charging multiple teens in connection with making school threats around schools in South Carolina, said agents.

The South Carolina Law Enforcement Division (SLED) said 21 minors have been arrested in connection to school threats. SLED officials said they are aware of more than 60 threats targeting schools throughout 23 countires since September 4,