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Massachusetts teen accused of murdering math teacher pleads not guilty

During an arraignment hearing, 14-year-old Philip Chism, pleads not guilty to charges of murder, aggravated rape and armed robbery, in the death of his math teacher, 24-year-old Colleen Ritzer.

The 14-year-old Massachusetts boy accused of slitting the throat of his math teacher in a school bathroom pleaded not guilty to murder and other charges Wednesday.

Nicolaus Czarnecki / Zuma Press

Philip Chism, 14, is accused of murdering teacher Colleen Ritzer, 24.

Philip Chism, accused in the Oct. 22 slaying of Colleen Ritzer, 24, is facing murder, aggravated rape and armed robbery charges.

Chism, who is charged with murder as an adult, appeared stoic during his court appearance just after 2 p.m. Wednesday, which ran for just 15 minutes.

Ritzer, a beloved teacher at Danvers High School, was discovered in the woods near the school along with a note reading: "I hate you all."

She was naked from the waist down and her body had been "sexually staged," according to court documents released last month. 

Teacher Colleen Ritzer

A law enforcement source told NBC News that Ritzer's throat was slit from the back with a box-cutter in a second-floor bathroom at the school. Her body was then taken from the campus in a recycling bin, dumped in the woods and covered with leaves, the source said.

Chism had already pleaded not guilty in district court, but the gruesome case was transferred to Superior Court after he was indicted in November, according to the Associated Press. His attorney consented Wednesday to a prosecution request that he remain held without bail.

Authorities have yet to disclose a motive for the teacher's brutal murder.

Chism's attorney has declined to comment, according to the AP.

The Associated Press contributed to this report.