NEW YORK (AP) — New York City’s mayor says “it’s very troubling” that at least nine jail inmates committed suicide after safeguards designed to protect them weren’t followed.

The Associated Press reported on the lapses Friday after obtaining investigative documents via public records requests.

Mayor Bill de Blasio says the findings are an “indication of what has been wrong for a long time.”

Investigators cited communication breakdowns, sloppy paperwork and inadequate mental health treatment as some of the factors in the deaths.

De Blasio says the findings are more evidence of how jails are often used as a “substitute for a real mental health system.” He says that’s “unacceptable.”

The city Correction Department says it is taking more steps to prevent suicides, including more communication between mental health workers and jail guards.

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