Transcript for New Twist in Deadly Shooting at Delta State
We're going to turn now to that deadly shooting on a college campus in Mississippi. Police say the gunman showing up and shooting a popular professor. And tonight, a possible motive. Students with their hands in the air, evacuating after the gunman opened fire, killing that teacher. Students using desks to bier cade their doors. Tonight, authorities say that professor wasn't the only person he killed before taking his own life, leaving behind a better with the words, "I'm so very sorry." ABC's Steve osunsami again on the case tonight. Reporter: Tonight, Mississippi police are releasing this disturbing call they received from Shannon lamb. The 45-year-old university geography intruck or the who investigators say first killed the woman he was living with. What's going on there? I shot my wife last night. Reporter: And then drove 300 miles to delta state university, where they say he shot and killed history professor Ethan Schmidt. Police say he called in the first killing after 10:00 A.M., just minutes before he walked into a classroom building and shot his colleague to death, sending the campus into a panic. Okay, sir, what is your name? Um -- that's all I feel like saying right now. Just go and take care of her. Reporter: Investigators found 41-year-old Amy Prentiss dead from a gunshot wound to her head. They say he left this handwritten apology, saying "I am so very sorry, I wish I could take it back. I loved Amy and she is the only person who ever loved me." Lamb killed himself as police were closing in. Tonight, they're still not sharing a motive for either shooting. David?
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