Federal and state officials say they have documented glaring flaws in the child welfare system at the Spirit Lake Indian Reservation in North Dakota, contending that while child abuse there is at epidemic levels, the tribe has sought to conceal it.
The problems uncovered by medical and social services administrators include foster children on the reservation who have been sent to homes where registered sex offenders live and a teenage female sexual-abuse victim who was placed in a tribal home and subsequently raped.
The tribe, according to federal officials, also hired a children's case worker who had been convicted of felony child abuse and employed another social worker who discovered a 1-year-old child covered with 100 wood ticks but did not take the child to a hospital.
The conditions led the State of North Dakota to take the unusual step this year of suspending financing for 31 tribal children in foster care.
Concerns about the children of Spirit Lake, which is in a remote area of northeastern North Dakota, extends to minors outside the social services system as well. In May 2011, a 9-year-old girl and her 6-year-old brother were found dead, raped and sodomized, inside their father's home on the reservation, a federal official said. By the time their bodies were discovered beneath a mattress, the children may have been dead for as long as three days.
The tribe, according to federal and state administrators, has not conducted required background checks before placing foster children, failed to make mandated monthly visits to children in foster care and illegally removed foster children from homes and placed them elsewhere without determining that the new homes would be safe.
Unease about the tribe's ability to adequately safeguard children has escalated in the past several weeks after two scathing, detailed e-mails were sent by federal officials to their superiors at the Department of Health and Human Services, alleging misconduct by reservation officials.
In a June 14 e-mail sent to his managers in Washington, Thomas F. Sullivan, the regional administrator for the Administration for Children and Families for six states, called on the government to declare a state of emergency at Spirit Lake, cut off the reservation's federal financing and charge the tribe's leader with child endangerment to combat what he described as "daunting" child abuse being covered up by the tribe.
The Spirit Lake reservation, like many Indian reservations across the country, has for years suffered from disproportionately high rates of child abuse and neglect, paired with accusations that abuse is underreported and minimized by tribes and infrequently prosecuted by federal authorities.
American Indians make up 9 percent of North Dakota's population, but Indian children constitute nearly 30 percent of the state's child abuse victims, a 2009 study by the Department of Health and Human Services found.
While statistics related to abuse at Spirit Lake are not public information, federal officials believe that the reservation has an even more significant child abuse problem than others in Indian Country. As one indication, the reservation is home to 38 registered sex offenders out of a population of 4,500, according to Justice Department figures -- a far higher proportion than in most cities and towns in the United States.
The recent e-mails from two highly respected government officials to the health department's Washington headquarters present a picture of a reservation hierarchy more intent on masking rampant child abuse than on ensuring the safety of children.
"The leadership of the Spirit Lake Nation as well as those who are responsible for delivering services on that reservation, by their actions as well as their inactions, have failed in their most basic responsibility to protect children," Mr. Sullivan wrote. "They have hung signs at the borders of the Spirit Lake Nation, 'Pedophiles Welcome.' They have made these signs operational by firing professionally qualified staff, directing their replacements to ignore reports of abuse and neglect, refusing to prosecute the most egregious cases of abuse."
While the tribe's leaders have not actually placed such signs on Spirit Lake, a clearly exasperated Mr. Sullivan also called for Roger Yankton Sr., the tribe's president, to be charged with a federal crime, saying Mr. Yankton has allowed children to continue to be harmed without addressing the problem.
The second e-mail, written in April by Michael R. Tilus, the director of behavioral health at the federally financed Spirit Lake Health Center, came below a subject line that read "Letter of Grave Concern." Dr. Tilus said that child abuse on the reservation was "epidemic" and that he had "no confidence" in tribal leadership "to provide safe, responsible, legal, ethical and moral services to the abused and neglected children of the Spirit Lake Tribe."
Tribal officials did not return phone calls seeking comment.
Mark Weber, a Health and Human Services Department spokesman, said the agency was working with the tribe and other agencies "to address concerns regarding the Spirit Lake Tribe's Social Service Department."
Nedra Darling, a spokeswoman with the federal Bureau of Indian Affairs, said the agency, which oversees some of the tribal programs, "has made it a top priority to address deficiencies with the Spirit Lake Sioux Tribal social services program" and plans to "take immediate actions to meet the needs of children on the reservation."
The agency, Ms. Darling said, is "conducting a comprehensive review" of tribal social services and plans to send a social worker to provide oversight and technical assistance.
Scott Davis, executive director of the North Dakota Indian Affairs Commission, said he had recently met with tribal leaders and believed that many of the tribe's problems were related to the departure of an employee who had been responsible for filing cases.
"I assume things are on track now," Mr. Davis said.
Timothy Q. Purdon, the United States attorney for North Dakota and one of the recipients of the e-mails, said he had insisted on holding a meeting with Bureau of Indian Affairs officials within the next few weeks.
Mr. Purdon said his office had prosecuted only a handful of child abuse cases from the reservation in the past year, but acknowledged that others might not have reached the attention of law enforcement if the tribe did not report the crimes.
"This certainly raises concerns for us about the social service function on Spirit Lake," he said. "I want to meet with B.I.A., agency to agency, and say, 'What are you doing to make sure we're responding to this appropriately?' "
This article originally appeared in The New York Times.