Fourteen-year-old Philip Chism was arrested in the murder of 24-year-old teacher Colleen Ritzer in Danvers, Mass., and was charged as an adult on Wednesday in court, Fox News reported. He pleaded not guilty in court and was held without bail. The Boston Herald added the judge approved a motion for Chism to be mentally evaluated.

The student did not come home from school on Tuesday, the news site said, and was found wandering Route 1 by Topsfield police early Wednesday, according to authorities. In the afternoon he appeared in Salem District Court, where his defense attorney argued the proceedings should be closed and that her client should be allowed to stay hidden because of his age, but the judged refused the request.

Ritzer, of Andover and a Danvers High School teacher, was found dead in the woods behind the school. According to Essex County District Attorney Jonathan Blodgett, she never came home from work on Tuesday and did not answer her cell phone. Authorities first found blood in a bathroom on the second floor of the school and then found the body.

Blodgett didn’t reveal just how Ritzer died or if the victim and suspect knew each other. There is no reason to believe there is another killer, authorities said.

Joe Spanos, a former teacher at Andover High School, knew Ritzer for about 10 years said she was the type of person a parent would want his daughter to be. "She was beautiful on the inside and out," he told FoxNews.com. "She's not a fighter. She probably never saw it coming."

Students were notified about the murder via a robo telephone call Wednesday morning, Kendall Meehan told the Boston Herald. "It's just terrifying," she said. "Nothing like this ever happens in Danvers."

Ritzer is the second teacher to be allegedly killed by a student in the U.S. this week after a Sparks, Nev., middle school teacher was shot and killed by a 12-year-old boy on Monday.