HOUSTON -- An attorney for an 18-year-old accused of fatally shooting 10 people at a Texas high school said federal prosecutors have filed 11 charges against the former student after previously indicating they would not.

Attorney Nick Poehl said he doesn't know what charges Dimitrios Pagourtzis is facing because the federal case is sealed as a result of Pagourtzis being a minor when the shooting occurred last year.

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Pagourtzis appeared in federal court in Galveston on Monday afternoon.

A spokeswoman for the U.S. attorney's office in Houston declined to comment. Family members of those killed in the shooting and many of the injured say they're grateful federal charges were filed.

Pagourtzis has been charged with capital murder in state court for the May 18, 2018, shooting at Santa Fe High School in Galveston County.

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