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GREENSBURG, Pa. (AP) – A prosecutor and defense attorney say plea negotiations are occurring in the case of a now-20-year-old charged with stabbing 20 fellow students and a security guard at his suburban Pittsburgh high school.

Defense attorney Patrick Thomassey told the Tribune-Review Wednesday there is a “good chance” the charges against Alex Hribal will be resolved before his trial, which is scheduled to begin Nov. 13.

Hribal faces 21 counts each of attempted homicide and aggravated assault, plus a weapons charge, for slashing his way through the hallways of Franklin Regional High School in Murrysville before classes began on April 9, 2014.

Thomassey acknowledges Hribal committed the crimes and tried to have his client declared legally insane, but failed to convince a judge of that.

Westmoreland County District Attorney John Peck confirmed the plea discussions.

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