Convicted Chicago Mob hitman put in solitary

The Chicago Sun-Times reports:

Mob killer Frank Calabrese Sr., who once threatened in open court to kill a prosecutor, has been placed under tough lockdown measures usually reserved for terrorists at the Metropolitan Correctional Center after allegedly threatening again to kill the same prosecutor, the Chicago Sun-Times has learned.

Calabrese Sr., 74, has been placed in solitary confinement since last month and is extremely limited in whom he can talk to, in an apparent attempt by the feds to stop him from communicating any orders for outsiders to carry out.