More lurid allegations were leveled against Shattuck-St. Mary’s School in a lawsuit filed Monday that accuses the school of turning a blind eye to the sex games and sexual abuse allegedly perpetrated by former teacher Lynn P. Seibel.

The suit, filed on behalf of an unnamed plaintiff who attended the private college-preparatory school from ages 13 to 18, claims Seibel sexually abused him several times between 2000 and 2003. During that time, the student lived in a dormitory supervised by Seibel, who lived in an apartment on the first floor with his family.

The lawsuit, filed in Rice County District Court by St. Paul attorney Jeff Anderson, accuses the Faribault, Minn., school of negligence, negligent supervision and negligent retention and asks for more than $50,000 in damages.

The school denied the allegations.

“We are disappointed that Mr. Anderson has rushed to file this lawsuit, as it makes accusations about our school without knowing, or choosing to ignore, important material facts,” the school said in a written statement. “Its allegations of negligence are unfounded and misdirected and we’re confident of our ability to demonstrate those truths.”

Seibel, 71, taught drama and was a dorm parent at Shattuck-St. Mary’s for 11 years. He resigned after school officials found child pornography on his computer. He was charged last October with 17 felony counts for the alleged sexual abuse of six male students from 1999 to 2003 and possession of child pornography in 2003. The school never reported the child pornography to authorities.

Seibel’s attorney, James Martin, was out of town and not available for comment Monday.

In its statement, Shattuck-St. Mary’s said the plaintiff in the civil lawsuit apparently is not one of the named victims in the criminal case.

“We have no record of him ever reporting an incident of sexual misconduct by Mr. Seibel while he was a student or in the 10 years since he graduated,” the statement said.

According to the lawsuit, administrators at Shattuck St. Mary’s were told at least two times about inappropriate sexual conduct involving Seibel and students, yet did nothing. Those included:

In the fall of 2000, teacher Seth Hedderick encountered naked male students in the dorm hallway, the lawsuit says. When Hedderick asked about their clothes, the boys told him, “You can’t have clothes on, it’s NDP” — “naked dance party” — and “It’s OK, Mr. Seibel is in the showers with us.”

Hedderick told headmaster Gregory Kieffer the next day, the suit says. He also told board members about Seibel and his “naked dance party.” Neither Kieffer nor the board members did anything, according to the suit.

During the 2000 school year, a student reported to Kieffer he was sexually abused by Seibel, but Kieffer did nothing, the suit said., The lawsuit also alleges that Seibel held “group sessions, which consisted of Seibel organizing the boys into an on-campus dorm room to watch pornography and masturbate” and engaged in various other sexually graphic discussions and games with students.

The suit comes after the Legislature in May passed a law allowing victims of child sexual abuse more time to bring claims as adults.

A trial date has not been set in the criminal case, and Seibel is free on $200,000 bail A contested omnibus hearing is scheduled for June 24 in Rice County. A contested omnibus hearing allows the defense to challenge probable cause, evidence or statements a defendant has made to authorities.