NEW BEDFORD - Sen. Mark C.W. Montigny is calling for an investigation of the state Department of Social Services for failing to remove a 3-year-old girl from a New Bedford home until nearly four months after the agency was alerted to possible abuse.

Sen. Montigny, D-New Bedford, said the handling of the alleged abuse by the girl's mother and her boyfriend follows a history of slow responses by DSS, and there needs to be an outside review.

"The DSS needs to be investigated as vigorously as this couple," Sen. Montigny said Friday.

In what is described as one of the worst child abuse cases in memory at Boston Children's Hospital, the girl suffered a mutilated ear and a lip that is permanently scarred by human bites. Her mother, Jessica L. Silveira, 26, and the mother's boyfriend, Bryan M. James, 34, were arrested Wednesday.

Rep. Antonio F.D. Cabral said Friday that he was not yet ready to call for an independent investigation, but he wants DSS commissioner Anthony "Angelo" McClain to give a report to legislators.

"I would like to give an opportunity to the new commissioner to come back to us and tell us what he thinks went wrong here, and depending on the assessment of the new commissioner, proceed from there," said Rep. Cabral, D-New Bedford.

Dr. McClain said his agency's original investigation in January did not suggest a serious case of abuse. If it had, he said, they would have pursued the matter more aggressively at the outset.

Mr. James faces one charge of mayhem, one charge of assault and battery on a child with injury resulting, and one charge of assault and battery on a child with substantial injury. The girl's bite injuries were allegedly inflicted by Mr. James as punishment for wetting her pants.

Ms. Silveira is accused of permitting substantial injury to a child and intimidating a witness. She allegedly gave misleading information regarding the true identity of her boyfriend.

Sen. Montigny said the agency should have moved faster to take the girl and her 5-year-old brother into custody as a precaution. He said the agency has in the past failed to aggressively address suspected abuse.

"When you have a known situation - and this happens over and over at DSS - it's deeply disturbing, and it needs to stop," Sen. Montigny said.

Dr. McClain said in a telephone interview that the girl and her brother are in foster care, and DSS is working with medical personnel to make sure she receives the necessary care. He said it's too soon to tell whether the children will end up in the care of extended family or remain in the foster-care system.

The agency first became involved with the family about a week before an injury report was filed in January. Social workers investigated reports the father, Eric Offley, a registered Class 3 sex offender, was making unsupervised visits with the children, Dr. McClain said. Mr. Offley's sex offenses do not involve Ms. Silveira's children, he said.

Officials were able to confirm that the father was not making those visits.

The girl was brought to a dentist in January with some swelling in her mouth, police Sgt. Pamela Mello said. The dentist called the police to the office, and police recommended that she go to the hospital. She was transported to St. Luke's, Sgt. Mello said.

Both police and DSS conducted an investigation at this point.

DSS found no evidence of child abuse, after both the child and the mother blamed injuries on a fall, and a doctor did not believe they were caused by an adult. The agency continued with its investigation out of concern over a possible lack of parental supervision, Dr. McClain said.

"At that point, the concern was more supervision and neglect," he said.

Sgt. Mello said police determined there was no evidence to pursue criminal charges, also based on medical evidence, but that did not rule out a future investigation if new evidence emerged.

"The case was basically placed on hold until which time additional evidence was made available to pursue charges or additional evidence was made available to close the case completely," Sgt. Mello said.

Police spokesman Capt. Richard Spirlet said police became involved in the case again in May as a result of DSS' subsequent investigation. Between January and then, the case was entirely in the hands of DSS, Capt. Spirlet said.

"We did everything we were supposed to do by law," he said of the initial investigation. "We made a report and turned everything over to DSS."

>From mid-January to the end of March, DSS made 10 attempts, including unannounced visits and letters, to contact Ms. Silveira. When DSS finally located Ms. Silveira during an unannounced visits, she told them the child was staying with her grandmother, Dr. McClain said. He could not immediately answer why social workers were not sent to the grandmother's home.

At that time, the agency scheduled another meeting in April, but the mother was not at home for the follow-up meeting, Dr. McClain said.

About the same time, DSS asked a judge to give the agency temporary custody of the children. On May 3, the children were placed in DSS care and have since remained together in a foster home, according to a DSS statement.

Not everyone is convinced the agency acted quickly enough.

Authorities should have pressed Ms. Silveira to show them the child, because there were warning signs of a serious problem, said Jetta Bernier, executive director for Massachusetts Citizens for Children.

There was a report of abuse from a physician, the child is particularly young and vulnerable, and the mother told social workers the child was not home, Ms. Bernier said.

"Everyone should have been running around trying to find this child," Ms. Bernier said. "This child could have easily been a fatality."

Asked if there will be any changes following this incident, Dr. McClain said the agency will emphasize that children's safety comes first. The agency will provide social workers with more guidance for identifying situations when they need to dig deeper for information and where to look.

"We're going to work to make sure our focus is on our core mission of keeping children safe," he said.