( CNN ) -- A teenage student is facing a first-degree murder charge , with police saying that he followed through on a plan to kill the principal of his small private school in Memphis , Tennessee . Eduardo Marmolejo was charged in the death Wednesday of 49-year-old Suzette York , the Memphis Police Department said in a statement Thursday . A detention hearing was held on Thursday , during which Magistrate Judge Sheldon McCall ordered the suspect held without bail and also ordered a mental evaluation , said Chief Probation Officer Barry Mitchell of the Memphis and Shelby County Juvenile Court . Court-appointed defense attorney Autumn Chastain told reporters Thursday that `` it 's difficult for everybody right now . '' `` It 's just a very serious allegation , '' Chastain said . `` We need to know everything that 's going on in the case . '' Police said the suspect is 17 years old , while Mitchell said he is 16 . CNN normally does not identify juveniles charged with crimes unless the juveniles are charged as adults . However in this case police have released his name under a Tennessee law that allows them to publicly identify juveniles charged with first-degree murder . Once the police publicly identified the suspect , CNN and other national and local media have reported his name . York was found Wednesday lying in a pool of blood at Memphis Junior Academy , according to the city fire department . Police , who responded to a call at 11:15 a.m. , added that she was pronounced dead at the scene , after succumbing to `` multiple stab wounds . '' Memphis Police Director Toney Armstrong told CNN on Thursday that the suspect `` has been carrying a grudge all summer long '' because the previous school year he 'd been switched out of a class that he liked . `` Basically , he conspired all summer as to how he was going to get revenge , '' Armstrong said . According to Memphis police , Marmolejo told investigators `` that he did not like ( York ) and that she had made him angry . '' Then he allegedly acted on his plans Wednesday , during the first week of school . `` He found himself alone in a classroom , ... and he attacked Ms. York , stabbing her multiple times resulting in her death , '' said Armstrong . The city 's police chief said authorities have no indication Marmolejo conspired with anyone , either in the planning or in the execution of the alleged crime . He added , `` From what we 've been told , ... there were no red flags '' to suggest the suspect posed a danger to others or to himself . York , who had been the principal of the school since 2008 , has a family in Memphis , said Marvin Lowman , communications director for the Seventh-day Adventist Conference in Goodlettsville , Tennessee . The school is affiliated with that church , said officials . `` It 's tragic all the way around , '' Memphis Mayor A.C. Wharton Jr. said outside the school . Former student Kristen Bridges described York as an exemplary biology and math teacher . `` Past the teaching , she loved God , '' Bridges told CNN affiliate WREG . `` And she showed that in everything she did . '' Marmolejo 's next hearing , also in juvenile court , is scheduled for August 24 , according to Mitchell . CNN 's Rick Martin contributed to this report .
NEW : Memphis ' police chief says the suspect carried `` a grudge all summer '' and was looking for an excuse to kill again. The head of Memphis Junior Academy was found lying in a pool of blood . The teenager is held without bond after a juvenile court hearing , a probation official says .