Mother Charged Over Mass. Boy's Possible Homicide (VIDEO)

A Massachusetts family who was receiving state social-services has been charged for not informing the police that their son had been missing since September, the Associated Press reported.

The child's mother and her boyfriend have been charged; a social worker and the worker's supervisor have been fired. Last seen by relatives on Sept. 14, 5-year-old Jeremiah Oliver's disappearance was recently discovered by the police. A prosecutor is treating Jeremiah's case as a possible homicide, AP reported.

Department of Children and Families Commissioner Olga Roche called it a "deeply concerning case of neglect and abuse." After a report of negligence was filed to the agency in the fall of 2011, the Fitchburg boy's family had been receiving services from the department, AP reported.

In June, the social worker was informed by Jeremiah's day care that his mother said it was his last day at school. He would be going to Florida to live with his grandmother, officials said. According to the AP, the officials said the social worker failed to confirm the information and conduct required checks.

"This case represents a serious failure on the part of the social worker and supervisor assigned to the family," Roche said in a written statement Tuesday. "The social worker assigned to this case did not conduct the required in-person, monthly checks on the family, as required by the Department; and the supervisor failed to enforce that policy."

Two employees "have been terminated," Roche said.

The department is working with State Police and prosecutors on the missing boy's case. Both cases of the social worker and the supervisor are currently being reviewed, AP reported.

Jeremiah's mother Elsa Oliver, 28, was charged with two counts of reckless endangerment of a child and two counts of being an accessory after the fact on Monday. She entered a plea of not guilty. A judge has ordered Elsa to undergo a mental competency evaluation.

Oliver's boyfriend, Alberto Sierra, 22, pleaded not guilty after being charged with two counts of assault and battery with a dangerous weapon and two counts of assault and battery on a child. Oliver's two other children have been placed in the custody of the Department of Children and Families, the AP reported.