(CNN) -- After failing to find her teenage son on the grounds of Danvers High School, Diana Chism called police in the small northeastern Massachusetts town where she lives with her three children. The call came on 6:34 p.m. on October 22 -- one in a long series of contacts and pieces of old-fashioned police work that helped crack a case that shocked the quiet New England town of 26,000. The mother's desperate call was one of the first items in a police affidavit that chillingly chronicled the killing of popular high school teacher Colleen Ritzer, 24, allegedly at the hand of shy student-athlete Philip Chism, 14.
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Court documents provide detailed timeline of case that shocked New England town
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Affidavit chronicles killing of popular teacher and the arrest of one of her students
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Prosecutors have said they will seek to try Philip Chism, 14, as an adult
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Colleen Ritzer, 24, was found, brutally slain, on October 23
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