A correctional officer and an inmate are dead following an altercation at a Pennsylvania prison. It happened Monday night at Luzerne County Correctional Facility in Wilkes-Barre, which is currently on lockdown, the AP reports. Luzerne County Manager David Pedri tells the Times Leader that the dead inmate is 27-year-old Tracy Gilliam, who he believes was in prison for failing to register as a sex offender. Pedri says the guard's family has asked for his name not to be released. "This guard went to work today believing that he would be coming home," he says. "And sadly, that didn't happen." Pedri says authorities will do all they can to make sure a "sad and tragic" incident like this doesn't happen again. State police and the county DA are investigating. (More Pennsylvania stories.)