FARIBAULT, Minn. (WCCO) - The Minnesota Bureau Criminal Apprehension and the Faribault Police department are investigating a former teacher accused of abusing students at Shattuck – St Mary’s School.

Seventy-year-old Lynn Seibel is charged with 17 counts of Criminal Sexual Conduct.

He taught drama at Shattuck from 1992 to 2003, and lived as a dorm parent with students.

Police Chief Don Gudmundson says the crimes are troubling.

“He would show up in the showers all the time when students were in the showers,” Gudmundson said. “At one instance, a young man came to the door, and [Seibel] said, ‘You don’t know how long I’ve waited for you to come.’”

Seibel was first investigated last June, when a 2001 graduate told police he was sexually molested by Seibel while he was a student.

Since then, five other victims are telling a similar story in which Seibel would play pornographic videos for a group of students, show them how to masturbate, touch their genitals and then measure them with a ruler.

BCA agent Drew Evans said the victims reported the abuse to the school.

“And they provided us with some documentation, saying that they had reported this but it is incomplete and difficult to understand what was provided to authorities in 2001,” Evans said.

One victim told police about alleged inappropriate touching that occurred inside Seibel’s on-campus apartment, where he lived with his wife and children.

In 2003, Seibel was investigated again after a faculty member found pornographic material on his computer. He was let go from the school.

“Certainly, if anybody has learned to be in possession of child porn – that would certainly be something to merit reporting to police or law enforcement authority…That did not happen in 2003,” Evans said.

Evans added that it’s illegal to not report abuse.

Seibel’s an actor who had a guest appearance on the CBS Show “Big Bang Theory.”

After police raided his California home in August, he told them about conversations he had with Shattuck-St. Mary’s Headmaster Dennis Brown in 2003.

“Lynn, you’re a sick man. You need to do something about it,” Headmaster Brown said, adding that he told Seibel to “get help.”

Seibel later admitted, “I exploited my authority and I exploited their trust, um, it seems. I never believed it was criminal.”

BCA agent Drew Evans called the investigation “active” and said more charges and more victims could be forthcoming.