NEW YORK -- The outside world knew Nixzmary Brown was a young girl in peril.
Her school saw the warning signs. So did neighbors. Even child welfare workers had been alerted -- twice.
This week, the 7-year-old was beaten to death in a Brooklyn apartment where she had been tethered to a chair with twine, investigators said. It was the fourth homicide in recent months involving a family monitored by the city's Administration for Children's Services, renewing concerns about the agency's ability to protect abused children.
As details of Nixzmary's torment emerged, child welfare officials acknowledged that the system had failed her. They launched an immediate review of thousands of other cases citywide.
John Mattingly, commissioner of the agency, said that in Nixzmary's case, the family was uncooperative, ignoring repeated phone calls from caseworkers and turning them away at the door. He said the agency should have obtained a court order to enter the home. ''We were in a position to have kept this from happening, and that did not happen," Mattingly said.
The girl's stepfather, Cesar Rodriguez is accused of binding, beating, and molesting her. He was arraigned Thursday on charges of second-degree murder, sex abuse, and child endangerment. Her mother, Nixzaliz Santiago, was arraigned on second-degree manslaughter and child endangerment charges.
Both were held without bail. Telephone calls to their defense lawyers were not immediately returned.
The girl was ''tortured," prosecutor Ama Dwimoh told reporters outside court. ''She was beaten repeatedly," Dwimoh said. ''She was bound like an animal."
Nixzmary's death followed that of three other children known to the agency: a 7-year-old died in October after her father allegedly kneed her in the stomach and beat her with a belt over two days; an infant drowned in November in a bathtub while his mother, who pleaded not guilty yesterday to manslaughter charges, allegedly listened to compact discs in another room; and a 1-year-old was allegedly beaten to death in December by his mother.
School employees had sounded the alarm about Nixzmary last year by reporting that she had been absent for weeks. Caseworkers spoke to her stepfather, mother, and the child and found no conclusive evidence of abuse, authorities said.
On Dec. 1, there was another report from someone claiming to have seen the girl with a swollen eye. A doctor concluded the injury was consistent with an explanation that she had fallen, but the agency kept the case open and tried to contact the parents.
Neighbors said that they also noticed unexplained injuries and that the child appeared malnourished and small for her age.