.The teenage son of a tribal chairman pleaded guilty Tuesday to a criminal charge for his role in shootings that left 10 people dead on an Indian reservation last March.

Louis Jourdain, 17, pleaded guilty to threatening interstate communications, according to a docket released by a federal court in St. Paul.

Two other charges — conspiracy to commit murder and conspiracy to commit offenses against the United States — were dropped.

The docket, some of which had been blacked out, gave few details of the charge, saying only that Jourdain used a computer to conduct interstate communications that "could be taken by an objective observer as threatening" sometime between Jan. 1, 2003 and March 2005.

Most of the proceedings involving Jourdain have been closed to the public because of his age, and the release of the docket marked the first time the charges were even disclosed.

Jourdain is the son of Floyd Jourdain Jr., the tribal chairman of the Red Lake Band of Chippewa. He was also a friend of 16-year-old Jeff Weise, who shot and killed nine people on the northern Minnesota reservation before killing himself.

Floyd Jourdain said authorities examined about 400 pages of text messages from his son that covered everything "from girls to music to video games to movies."

"Unfortunately, some of it might be perceived as threatening or inappropriate," he said. "And that is basically what he's decided that he is admitting to today."

The rampage started when Weise killed his grandfather and his grandfather's girlfriend, then went to Red Lake High School, where he killed seven people in the nation's worst school shooting since Columbine.

Jourdain was arrested a week after the shooting and remained jailed Tuesday. His trial had been expected to begin in mid-December in federal juvenile court.

Floyd Jourdain said his son "admits to his wrongheaded and inappropriate use of the Internet, but he does not accept responsibility for the 10 lives lost at Red Lake on March 21 because he is not responsible."

Carol Stillday Spears, whose 15-year-old daughter, Thurlene, was killed, said she was frustrated to hear that the more serious charges against Jourdain were dropped.

"I think he should be punished. I lost my baby over there," Spears said. Her two other teenage daughters do not attend the school because they are still scared.

Red Lake Principal Chris Dunshee said he hopes the plea "will lend to the healing process and not be something that will cause more divisiveness."

Messages left at the office of Jourdain's attorney, Jon Hopeman, were not immediately returned.

No sentencing date was set. In most cases, juveniles who are tried in federal court can only be held until age 21.

Karen Bailey, a spokeswoman for U.S. Attorney Tom Heffelfinger, said the law requires sentencing within 20 business days. She said Heffelfinger did not have anything else to say about the case.