A Missouri father is facing child abuse charges after allegedly shoving his fingers down his infant son's throat to make the baby stop crying.

Investigators say 19-year-old Robert Burnette of Wentzville also threw his 6-week-old son onto a bed, violently shook him and picked him up by the back of his neck. Police say the baby's mother watched without intervening.

The baby was listed in critical but stable condition Monday at a St. Louis hospital.

Burnette and the baby's mother, 20-year-old Megan Hendricks, were arrested last week. Both are charged with child abuse causing serious injury.

Neither Burnette nor Hendricks has obtained an attorney. Both are scheduled to appear in court Tuesday.

Wentzville Police Chief Kurt Frisz says the case was shocking because of the "outright savageness of the assault."