BURLINGTON, Vt. – The Vermont 12-year-old found dead last week near her uncle’s home was killed, a prosecutor said Monday.

Assistant U.S. Attorney Craig Nolan made the disclosure at a hearing at which the judge ordered the uncle, Michael Jacques, held until his trial on a federal kidnapping charge.

“He has a very serious criminal history demonstrating an extreme danger to the community,” Nolan said at the U.S. District Court hearing.

Jacques, 42, is accused of kidnapping Brooke Bennett on June 25. After a weeklong search, she was found in a shallow grave about a mile from his home in Randolph.

Nolan said the death was a homicide, but said nothing about how she died. State police say it could be up to eight weeks before autopsy results are available.

Because the girl was killed, prosecutors could seek the death penalty against Jacques if he is convicted. Federal public defender Michael Desautels did not ask U.S. Magistrate Judge Jerome Niedermeier to release Jacques.

Jacques is a registered sex offender. He was convicted in 1993 of kidnapping and raping a woman he supervised at a fast-food restaurant. He planned to initiate Brooke into a child sex ring after taking her from outside a Randolph convenience store on June 25, another underage girl who said she was a witness told authorities.

Brooke’s former stepfather, Raymond Gagnon, 40, is charged with obstruction of justice in the case. Gagnon of San Antonio did not contest his continued detention during a hearing earlier Monday in the same court. Gagnon graduated from the University of Maine in Orono in December 1990 with a degree in mechanical engineering technology.

Gagnon is accused of having someone throw out his laptop computer a week ago while authorities were searching for Brooke.

While he was in court, federal prosecutors in Alabama charged him 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. Gagnon also accessed the account that night, but denied changing the posting, according to the affidavit.

In announcing the pornography charge, federal prosecutors in Birmingham, Ala., said Gagnon acknowledged trying to access the account again from a public computer in the Cullman library “on or about” June 26, the next day.

The complaint in Alabama said Gagnon flew from San Antonio to Cullman that day and on to Burlington on June 27.