Updated 4:55 p.m. EST
(CBS/AP) DANVERS, Mass. - A 24-year-old Massachusetts teacher who was allegedly killed by one of her students had asked him to stay after school the day she was killed, a classmate said Thursday.
Fourteen-year-old Philip Chism, a student at Danvers High School, is charged with killing his math teacher, Colleen Ritzer. He was ordered held without bail at his arraignment Wednesday.
Sources tell CBS Boston that a box cutter was used to kill Ritzer and that her body was carried out of the school in a recycling bin.
Police say surveillance cameras and interviews with Chism indicate Ritzer was murdered and then left in the woods near the school, reports the station.
Essex County District Attorney Jonathan Bodgett has said Ritzer's body was found early Wednesday morning. She had been reported missing Tuesday night.
Prior to discovering the body, investigators found blood in a second floor bathroom of the high school, the D.A. said.
Rania Rhaddaui, a student who sat two seats away from Chism in Ritzer's math class, says Chism was drawing in a notebook rather than taking notes Tuesday. Rhaddaoui says she heard Ritzer ask Chism to stay after class, the last period of the school day.
"She came over and said, 'I didn't know you draw,' and he said, 'yes,' then later on, she said, 'Can you stay after with me?'" Rhaddaoui said. "Obviously, he stayed after because when I was leaving, he was still at his desk."
She said Ritzer had scheduled a test for Friday, but she was unsure why exactly Ritzer asked Chism to stay after school.
Authorities are continuing to investigate the murder and have not publicly confirmed how the teacher was killed or what the motive may have been.
Chism had moved to Massachusetts from Tennessee just before the school year and was described by classmates as pleasant, but quiet.
A freshman student who was in Ritzer's class with Chism told Crimesider that as far as she knows, between the teacher and student.
"He was always quiet. ...He never talked to anyone," the girl, who asked to remain anonymous, said.
Chism was picked up by police early Wednesday morning as he walked along Route 1 in neighboring Topsfield. His attorney declined to comment outside court Wednesday and did not immediately return a call seeking comment Thursday.
Classes at Danvers High School are scheduled to resume Friday.