Maricopa County Sheriff Joe Arpaio is ordering all his jails to shut down Saturday in advance of an expected protest near prison grounds.
Several thousand activists will call on Arpaio to close Tent City, an extension of his jails opened in 1993 that can house more than 2,000 inmates.
During Saturday's security override, inmates will not be allowed to accept visits from family or friends for the entire day.
The protest march is scheduled for 6 p.m. Saturday in front of Tent City, located at 29th Avenue and Durango Road in Phoenix.
MCSO said it is preparing for as many as 4,000 activists to turn out.
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