(Faribault, MN)  --  The sexual abuse investigation at Shattuck-Saint Mary's School continues to grow.  Faribault Police Chief Don Gudmundson says investigators received a call from someone who said he was the victim of another sexual abuse involving another teacher at Shattuck-Saint Mary's in the late 1970s or 1980s.  Gudmundson says a third case involves a former Shattuck teacher who killed himself in 2008 after the school confronted him about a sexual relationship with a foreign exchange student.  Former drama teacher Lynn Seibel (SY'-bull) was charged Monday with 17 counts of criminal sexual conduct.  Several witnesses in the Seibel case plan to update their statements to police.