Police in Spotsylvania County say they’ve stopped a planned school shooting attack.

Authorities in announced at a news conference Saturday that two Riverbend High School students were being held at a juvenile detention center, charged with conspiracy to commit murder. Police did not release their names.

“Their plot was to phone in a bomb threat and then shoot people as they came out,” County Commonwealth Attorney Bill Neely said.

Police said plans started to unfold two weeks ago, when a School Resource Officer arrested and initially charged a 17-year-old male student for threatening violence over the internet.

An investigation then uncovered a 15-year-old boy who was linked to the planned attack, according to officials. Spotsylvania Sheriff spokesman Capt. Jeffery Pearce told CNN that the students had access to the weapons they said they would use in the incident.

Police say no other suspects are believed to be involved.

“We stopped them cold,” Capt. Pearce said.

The plot’s timing was not revealed but police said there was no immediate threat.

