WSI-Oak Ridge, a security contractor at the Y-12 nuclear weapons plant, confirmed that one of the guards on site during the July 28 security breach has been fired and others have been disciplined.

“One (security police officer) has been terminated and appropriate disciplinary action has been taken with the additional individuals,” Courtney Henry, a spokeswoman for WSI, a unit of G4S Government Solutions, said by e-mail in response to questions. The names of the guards and other details of the disciplinary actions were not released.

WSI earlier had stated that three guards were suspended and placed on restricted duty status following the incident, in which three protesters entered the high-security installation in the predawn darkness and cut through fences to reach the plant’s storage compound for bomb-grade uranium. The storehouse was defaced with spray-painted protest messages and splattered with human blood before guards arrived at the scene around 4:30 a.m.

The National Nuclear Security Administration was highly critical of the guards’ response during the incident, saying Y-12’s protective force was slow to respond to alarms and — even when they reached the scene — failed to take appropriate steps to secure the Plowshares protesters.