A young Bronx mother accused of killing her baby boy pleaded not guilty to murder and assault charges during her arraignment Wednesday.

Police found 7-month-old Cashmir Randall unconscious Monday night in an apartment on East 222nd Street. The child was pronounced dead shortly after from what the medical examiner later determined to be blunt trauma to his head.

The baby?s mother, 21-year-old Naisha Riley, was taken into custody and charged with murder and assault. Riley allegedly told detectives in a statement that her son would not stop crying, so she shook the baby at least four times, picked him up by the jaw and punched him in the head repeatedly. Riley mentioned her son was whimpering and at one point possibly stopped breathing. Autopsy results show the baby was shaken so violently that he suffered whiplash and a brain hemorrhage.

Riley?s mother and other family members say she is a compassionate mom not capable of killing her baby. Riley?s aunt, Ciara Lawrence, believes her niece may have been forced to confess by police officers.

The district attorney will present Riley?s case to the grand jury June 15 to determine if it will go to trial. Reports say Riley also has a 2-year-old daughter, who is now in the custody of child protection services.