This is the second day of operation of the system, according to the press. However, a restricted version of the same FRS was used for 15 days during the Carnaval festivities with no alarming failures and reportedly resulted in a few arrests.
It has now been deployed in 25 locations in Copacabana. (Anedoctally, I live here and can't tell you where they are - the equipment, cameras, etc. must be well hidden, or I'm terrible at spotting them).
Source, in Portuguese: "Facial recognition fails in its second day and innocent woman confused with criminal is arrested" https://oglobo.globo.com/rio/reconhecimento-facial-falha-em-segundo-dia-mulher-inocente-confundida-com-criminosa-ja-presa-23798913
Related previous submission (with zero comments): https://news.ycombinator.com/item?id=19074434