Ohio is replacing several prison transport vans, adding cameras to them and installing individual segregation cells on board for the most violent and dangerous inmates, the state prison system said Friday.

The state will also load inmates into vans based on three levels of risk and will transport inmates alone who represent "an extraordinary safety risk," the prison system said.

The changes announced by the Department of Rehabilitation and Correction follow an investigation into the 2017 strangling death of an inmate riding in a prison van during a medical run.

Prisoner Casey Pigge pleaded guilty in September to killing fellow inmate David Johnson with a restraining chain as they rode on a transport van.

"I guess you never seen that on a bus before," Pigge boasted to the surviving inmates after Johnson's killing, according to highway patrol records. Johnson was serving an eight-year sentence for sexual battery.

Pigge was sentenced to 25 years behind bars for killing Johnson. Pigge is also serving a life sentence for using a brick to kill cellmate Luther Wade in 2016, and 30 years to life for fatally slitting the throat of his girlfriend's mother in 2008.

Pigge's violent behavior wasn't over after killing Johnson, however, according to prison authorities. Pigge and another inmate stabbed a prison guard multiple times in February, according to the prison system and the union representing Ohio prison guards.

Other changes to transport policies announced by the prison system Friday include:

— Increasing hands-on training for prison guards transporting inmates and expanding random checks of inmates' van restraints.

— Adding GPS tracking to vans.

— Directing wardens to ensure all guards transporting inmates are properly trained.

___

Andrew Welsh-Huggins can be reached on Twitter at https://twitter.com/awhcolumbus .