The Arizona Department of Child Safety (DCS) said it previously investigated allegations surrounding the family in Thursday's triple homicide at a Phoenix home.
Police said three boys were found dead in a home near Interstate 17 and Bell Road. Their mother, Octavia Rogers, 29, is accused of stabbing them to death and stuffing their partially dismembered bodies in a closet.
Police said Rogers also stabbed herself and then tried to drown herself in a bathtub. She remains in a local hospital.
The children have been identified as Jaikare Rahaman, 8, Jeremiah Adams, 5, and Avery Robinson, 2 months.
According to a statement from DCS Director Gregory McKay, the agency received allegations of a child with a small abrasion on his forehead in 2010, but investigators were unable to locate the family.
McKay said in 2011, DCS investigated an allegation of child neglect due to marijuana odor coming from the family home. The mother was referred for family preservation services, a DCS-funded contract with a private provider. DCS said she refused to receive the services.
"There was no reason or legal grounds to take the children into emergency state care and the case was closed as unsubstantiated," McKay said in the statement released Friday morning.
Earlier this year, DCS investigated an allegation that the mother gave birth to a baby exposed to marijuana. According to the statement, the investigator found the children to be safe and referred the mother for services, again contracted and paid for by DCS. The mother did not participate in the services.
McKay said there was no reason or legal grounds to take the children into emergency state care. The case was substantiated and closed, according to his statement.
DCS is assisting the Phoenix Police Department in the ongoing investigation.
"It is a sad day as we reflect on the gruesome nature of what occurred," McKay said in the statement. "We grieve as a community, trying to understand why three innocent souls have been taken. We grieve as an organization, suffering the loss of children whom we knew. When a child is murdered, it's common to ask if something could have been done to prevent such a tragedy. At DCS, we ask ourselves those questions because we take the responsibility of protecting children very seriously. But our powers are limited; we cannot predict the future; and people, can at times, do awful things."
McKay said DCS will be conducting an internal review to ensure processes are employed to best protect children.
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