BURLINGTON, Vt.—A 12-year-old girl found dead last week in a shallow grave near her uncle’s home was killed, a federal prosecutor said Monday at an initial appearance for the uncle on charges of kidnapping the girl.

Michael Jacques, who is accused of abducting his niece, Brooke Bennett, was ordered held until his trial on a federal kidnapping charge. His attorney, Michael Desautels, did not ask U.S. Magistrate-Judge Jerome Niedermeier to release Jacques.

“(Jacques) has a very serious criminal history demonstrating an extreme danger to the community,” Assistant U.S. Attorney Craig Nolan said.

Nolan said Brooke’s death was a homicide, but he didn’t say how she was killed. No one has been charged with her death. State police say it could take eight weeks before autopsy results are available. Jacques could face the death penalty if convicted under federal law of kidnapping resulting in Brooke’s death.

Prosecutors say Jacques, 42, abducted Brooke on June 25. After a weeklong search, she was found buried about a mile from his home in Randolph, about 50 miles southeast of Burlington.

Jacques is a registered sex offender. He was convicted in 1993 of kidnapping and raping a woman he supervised at a fast food restaurant. Citing statements from another underage girl, prosecutors claim in an affidavit that Jacques tricked Brooke into thinking she was going to a party and instead took her to his Randolph home to initiate her into a child sex ring on the day she disappeared.

At a hearing in the same court earlier Monday, Brooke’s former stepfather, Raymond Gagnon, did not contest his continued detention on obstruction of justice charges related to the case. Gagnon, of San Antonio, is accused of having someone throw out his laptop computer a week ago while authorities were searching for Brooke.

Gagnon married Brooke’s mother in 2000, but they later divorced.

During Gagnon’s hearing, federal prosecutors in Alabama charged the 40-year-old with possessing child pornography at his former home in Cullman, Ala.

In affidavits filed in Vermont, the FBI said Jacques changed a posting to Brooke’s MySpace account the night she was reported missing.