Now, we have new details on the murder of that young teacher in massachusetts. One of her students has been charged. And abc's gio benitez has the story. Reporter: This morning, a danvers high school... See More
Now, we have new details on the murder of that young teacher in massachusetts. One of her students has been charged. And abc's gio benitez has the story. Reporter: This morning, a danvers high school student tells us math teacher colleen ritzer offered to help her alleged killer, just hours before her body was found. What exactly did she say to him? Can you stay after? Reporter: Can you stay after? Yeah. Can you stay after. Reporter: Ninth grader rania says she was in ritzer's final class on tuesday, sitting just two seats away from the accused murderer. Phillip chisel. He's been really quiet. Extra quiet. Reporter: Not unusual, she says. For the 24-year-old teacher, whose mantra is now in front of the school. Quote, being good to people is a wonderful legacy to leave behind. Law enforcement sources tell abc news, chism followed ritzer into the women's bathroom, killing her with a box cutter. Putting her body in a large recycling bin and moving her to the woods. The whole time, captured on camera, wearing a hat and gloves. Then, sources say, he changed clothes and went to a movie theater, where the manager said he bought a ticket to the woody allen film, "blue jasmine," before being found wandering on a highway later that night. He pleaded not guilty. The person you know and that description, does it match? No. That's why we're all so shocked. Reporter: Rania, to know you were in that final class of hers -- it haunts me. It haunts me all the time that i was in the building and that i saw him after school with her. Reporter: And the suspect's grandmother told abc news overnight, in florida, that the family has great sadness and regret for what happened here.
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