Isabella Guzman, 18, sent her mother a threatening e-mail with the message "You will pay", the day before she fatally stabbed her mother 79 times in Aurora, Colorado, according to court records filed last Friday. An autopsy showed the mother, 47-year-old Yun-Mi Hoy, died after being stabbed repeatedly in the face and neck, according to an arrest affidavit obtained by TV news station 7NEWS.
Isabella's stepfather, Mr Ryan Hoy, said his wife was attacked as she went to take a shower in an upstairs bathroom last Wednesday night.
Mr Hoy told police he was eating dinner downstairs when he heard a thumping sound upstairs and his wife calling his name.
He rushed upstairs and heard the shower running and tried to force open the closed bathroom door.
He caught a glimpse of Isabella, who pushed the door shut with her back and locked it.
Mr Hoy then saw blood flowing from under the bathroom door and called the police on his mobile phone, saying his wife was being attacked, the affidavit said.
He said Isabella had a tense relationship with her mother and had been sent to live with her father, Robert Guzman, for some time.
Get The New Paper for more stories.