Curran-Fromhold Correctional Facility
© Reuters (file photo)Curran-Fromhold Correctional Facility in Philadelphia, Pennsylvania.
The Pennsylvania Department of Corrections has puts its facilities on lockdown after reports multiple staff members were sickened by unknown substances . This comes after a similar emergency in an Ohio prison.

"The safety and security of our employees is my number one concern,"John Wetzel, Pennsylvania Department of Corrections Secretary, said as he announced the lockdown.

"Our state prisons, especially, those in the western part of the state, have experienced recent incidents in which employees have been sickened and we need to get to the bottom of this issue now."

Effective immediately, all of the state's 24 prisons are locked down, all visits have been suspended, mailrooms indefinitely closed to non-legal mail, and staff have been instructed to don protective clothing and equipment, the department said on Wednesday.

Earlier on Wednesday, 24 people were treated by doctors from overdose symptoms at a prison in Ohio. Five nurses, 15 correctional officers, an inmate and several others at the Ross Correctional Institution felt sick after exposure to a substance, believed to be some kind of opiate. Those affected were given a special medication, used to quickly reverse opioid overdoses, called naloxone.

The reports came against the background of a massive, nation-wide prison strike, with inmates across 17 US states protesting inhumane conditions and prison labor, which they describe as "modern day slavery."