Massachusetts teen pleads not guilty to killing high school teacher

FILE - In this Oct. 23, 2013, file photo, Philip Chism, 14, stands during his arraignment for the death of Danvers High School teacher Colleen Ritzer, as his attorney Denise Regan speaks on his behalf in Salem District Court in Salem, Mass. The 14-year-old Massachusetts boy is set to be arraigned Wednesday Dec. 4, 2013 on murder, aggravated rape and armed robbery charges in the killing of his high school math teacher. (AP Photo/Boston Herald, Patrick Whittemore, File) (The Associated Press)

FILE - This undated file photo provided by the family shows Danvers High School teacher Colleen Ritzer, whose body was found behind the school on Oct. 22, 2013, in Danvers, Mass. In an indictment returned Thursday, Nov. 21, 2013, Philip Chism, 14, was charged with sexually assaulting and killing Ritzer, and stealing her credit cards and iPhone. (AP Photo/Courtesy of Dale Webster via the Lawrence Eagle-Tribune, File) (The Associated Press)

A 14-year-old Massachusetts boy has pleaded not guilty to murder, aggravated rape and armed robbery charges in the killing of his high school math teacher.

Philip Chism is accused in the Oct. 22 death of Colleen Ritzer, a popular teacher at Danvers High School. Ritzer's body was found in woods near the school with her throat slit and a note reading, "I hate you all."

Chism had already pleaded not guilty in district court, but the case was moved to Superior Court after he was indicted last month. His attorney agreed Wednesday to a prosecution request that he remain held without bail.

Chism had recently moved to Massachusetts from Clarksville, Tenn.

Police haven't released a motive for Ritzer's killing. Chism's attorney has declined to comment. Ritzer's family was in court Wednesday.