Updated at 2:52 p.m. ET

A Pennsylvania judge has dismissed the most serious charges filed against 11 members of the Beta Theta Pi fraternity in the hazing-related death of Timothy Piazza.

Judge Allen Sinclair dismissed involuntary manslaughter charges filed against the fraternity brothers.

But he allowed new charges of "conspiracy to commit hazing" to proceed against some of the fraternity brothers.

Pennsylvania Attorney General Josh Shapiro said in a statement that he was "disappointed by the decision" and is "assessing our legal options."

"We filed these charges after a comprehensive review of the case," Shapiro said. "That review is ongoing. We will move forward with our case and the charges that were held for trial today. I am disappointed by the decision of the Magisterial District Judge and we are assessing our legal options. My office is committed to seeking justice for Timothy Piazza and his family and holding responsible individuals accountable for their actions, consistent with the law and the evidence in this case."

Through its attorney, Thomas Kline, the Piazza family also echoed its disappointment but said it was "heartened" that various other charges were either added or are continuing to be pursued:

"While disappointed that the refiled involuntary manslaughter charges against the fraternity brother criminal defendants were again not sustained by Magistrate Judge Sinclair, the parents of Tim Piazza are heartened that the important newly filed conspiracy charge has now been added and will move forward to trial along with the charges of reckless endangerment and hazing. These charges carry with them significant penalties, including substantial jail time. Jim and Evelyn Piazza are optimistic that the Pennsylvania Attorney General will obtain a full measure of justice on behalf of their son, and this prosecution will eventually deter this kind of abhorrent conduct."

Among the defendants is Luke Visser, who allegedly ran a beer pong table at the Beta Theta Pi house the evening Piazza was injured. In his case, conspiracy to commit hazing charges were dismissed by the judge, along with the more serious involuntary manslaughter charge.

Visser's attorney Theodore Simon thanked the judge for finding again that the most serious charges against his client should be dropped. Simon wrote in a statement to NPR, "This was a sad and tragic loss of life, but not every unfortunate tragedy should result in serious criminal charges."

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