A Federal Bureau of Prisons employee died after coming into contact with an unknown substance in the mailroom at the U.S. penitentiary in Atwater, California, according to a bureau spokesperson.

A Federal Bureau of Prisons employee died after coming into contact with an unknown substance in the mailroom at the U.S. penitentiary in Atwater, California, according to a bureau spokesperson.

A Federal Bureau of Prisons employee died after coming into contact with an unknown substance in the mailroom at the U.S. penitentiary in Atwater, California, according to a bureau spokesperson ...

An inmate at the Federal Correctional Institution in Bennettsville has died after an employee found him unresponsive in his cell early Monday morning.

A Federal Bureau of Prisons employee died after coming into contact with an unknown substance in the mailroom at the U.S. penitentiary in Atwater, California, according to a bureau spokesperson ...

A Federal Bureau of Prisons employee died after coming into contact with an unknown substance in the mailroom at the U.S. penitentiary in Atwater, California, according to a bureau spokesperson.

A Federal Bureau of Prisons employee died after coming into contact with an unknown substance in the mailroom at the U.S. penitentiary in Atwater, California, according to a bureau spokesperson.

Hans Neleman/Getty Images/STOCK (ATWATER, Calif.) — A Federal Bureau of Prisons employee died after coming into contact with an unknown substance in the mail room at the U.S. penitentiary in ...