>Teen, 17, 'was stabbed to death by his ex-boyfriend, 16, after breaking up with him to date a girl >Investigators said Jeremy Sanchez was killed by his ex-boyfriend >Sanchez allegedly recently broke up with the 16-year-old suspect to date a girl >The suspect is said to have called Sanchez and asked him to meet him by an L.A. river Tuesday night >Sanchez's body was found the next day when his father asked the suspect and another good friend to help him look for the teen >The suspect, who is not being identified because of his age, is being held in juvenile hall
