DANVERS, Mass. (CBS/AP) -- A 14-year-old high school student described by classmates as soft-spoken and pleasant was ordered held without bail Wednesday after being accused of killing a well-liked math teacher whose body was found in the woods behind the school.
Law enforcement officials recovered the remains of 24-year-old Danvers High School teacher Colleen Ritzer early Wednesday, Essex District Attorney Jonathan Blodgett said.
"We have no reason to believe that any other suspects are involved," Blodgett told reporters during a Wednesday morning news conference.
The teen was ordered held at his arraignment in adult court on a murder charge in Salem. He is due back in court Nov. 22.
His defense attorney argued for the proceedings to be closed and her client to be allowed to stay hidden because of his age. The judge denied the request.
CBS News is not naming the suspect at this time because of his age.
Police started investigating after Ritzer was reported missing late Tuesday night, because she had not returned home from work and was not answering her cellphone. Investigators found blood in a second-floor school bathroom and soon located the victim, he said. He did not say how Ritzer died.
"She was a very, very respected, loved teacher," Blodgett said, calling the killing a "terrible tragedy."
The boy also was reported missing Tuesday after not coming home from school. He was spotted walking along a road in neighboring Topsfield at about 12:30 a.m. Wednesday.
Ritzer had a Twitter account where she gave homework assignments, encouraged students and described herself as a "math teacher often too excited about the topics I'm teaching."
She was a 2011 graduate of Assumption College, a school spokeswoman said Wednesday. She graduated magna cum laude with a bachelor of arts degree in math, a minor in psychology and a secondary education concentration, according to the college's 2011 commencement program.
"I just remember seeing her in the hallway and she always had a smile, like 'hi' to everyone, and she was just an amazing person," Megan Papagelis, a Danvers High graduate, told CBS Boston station WBZ-AM.
"It's just shocking to see that this could happen," Papagelis told WBZ-AM. "Unbelievable."
Chris Weimert, 17, was a student in Ritzer's geometry class last year. He told The Associated Press she had taught at the school for two years and was a warm, welcoming person who would stand outside her classroom and say hello to students she didn't teach.
"She was the nicest teacher anyone could ever have. She always had a warm smile on her face," he said.
Weimert said the suspect, who he knew from seeing him around school, "seemed like a good kid." He said, "It really threw the whole town of Danvers a curve ball."
Kyle Cahill, a junior, said he knows the suspect from the soccer team. He said the 14-year-old moved to Massachusetts from Tennessee before the school year began and was a top goal scorer on the school's junior varsity team.
He called him a quiet, nice kid.
"He wasn't violent at all. He was really the opposite of aggressive," Cahill said.
Cahill said there was a soccer team dinner Tuesday night that the accused teen skipped, and team members were wondering where he was.
"We're all just a family. It just amazes me really," he said. "I'm just stunned."
Ryan Kelleher, a senior who also plays soccer, told the AP the arrest of the soft-spoken student didn't make sense to him.
"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," the 17-year-old said.
Kelleher took Ritzer's algebra class last year and said hello to her on Tuesday in the hallway. He said students related to the young teacher, who liked to wear jeans and UGG boots just like the students.
"She just loved to come to school and just teach and teach students and help them succeed," he said.
All public schools in Danvers, about 20 miles north of Boston, were closed Wednesday.
The high school's students were planning a candlelight vigil near the school Wednesday evening.
Ritzer is the second teacher allegedly killed by a student in the U.S. this week. A Sparks, Nev., middle school teacher was allegedly shot by a 12-year-old student on Monday.
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