The South Dakota State Penitentiary and the adjacent Jameson Annex have been placed on lockdown as of late Sunday night, with the Department of Corrections (DOC) stating that the duration of the lockdown is currently unknown. All visits, except for attorney meetings and previously scheduled special visits, have been canceled, and phone services for inmates may be temporarily disabled. The DOC has not provided specific reasons for the lockdown, indicating that it is related to facility security and operations, and they will not respond to further inquiries during this period. The facilities housed 1,262 inmates as of August 31, with previous lockdowns occurring earlier in the year following incidents of unrest. The DOC will release additional information through its website and social media if deemed necessary.