New details have emerged in the slaying of a beloved Massachusetts high school math teacher.
Two law enforcement sources "close to the investigation" told CNN's Pamela Brown that 14-year-old Philip Chism used a box cutter to kill Colleen Ritzer.
Ritzer's body was discovered in a wooded area behind Danvers High School on Wednesday.
Authorities believe that Chism went to a matinee showing of the new Woody Allen movie, "Blue Jasmine," shortly after murdering Ritzer, the Boston Herald Reports.
Students told the Associated Press they were shocked that Chism could have killed the popular educator.
"From what I know about him and seeing him every day, it just doesn't add up that he would do such a thing, unless this was all an act to fool somebody," Ryan Kelleher, 17, said.
Ritzer was reported missing on Tuesday after she didn't come in to work, Essex District Attorney Jonathan Blodgett told the AP.
CNN reports that Chism was also reported missing on Tuesday night. He was found walking along a highway later that night.
His arrest was made "based on statements by the suspect and corroborating evidence at multiple scenes," according to court documents obtained by the AP.
Police have yet to release a motive for the killing.
Related on HuffPost:
The body of Danvers, Mass., high school teacher Colleen Ritzer was found Wednesday, Oct. 23, following a search by police that began when she was reported missing the previous night.
"She was a very, very respected, loved teacher," authorities said of slain Danvers High School teacher Colleen Ritzer, whose body was found in woods behind the school Wednesday.
Philip Chism, 14, is suspected in the murder of teacher Colleen Ritzer. Chism appeared in court Oct. 23, and will be tried as an adult.
Murder victim Colleen Ritzer in an undated photo from MySpace.
Murder suspect Philip Chism in an undated photo.
Murder suspect Philip Chism in a photo released by Danvers Police.
Colleen Ritzwer in an undated family photo.
Colleen Ritzer in an undated family photo.
Colleen Ritzer in a family photo from Facebook, dated Mar. 13, 2013
An image with a quote posted by Colleen Ritzer to her Pinterest board about seven weeks before her murder.
An image with a quote posted by Colleen Ritzer to her Pinterest board about eight weeks before her murder.