UPDATE 5:10 p.m.: A 2-month-old child remains hospitalized on life support and his father is accused of putting him there.
Henry Morales, 25, was arrested Sunday and charged with child abuse and aggravated malicious wounding. Officials call it a case of shaken baby syndrome.
"The child suffered a number of injuries, a lot of which weren't recent injuries," said Paul Ebert, the Prince William County Commonwealth's Attorney.
Sources say Morales told police he was holding his newborn when he tripped on the stairs and fell on the baby. The sources say doctors discovered a previous rib injury.
Morales' two older children are in the custody of child services.
Prince William police say Morales is in the United States illegally. He is being held without bond pending a hearing in December.
Ebert says if the baby dies, Morales will likely face murder charges.
Prince William County police have charged a Manassas father after his infant son was critically injured.
Twenty-five-year-old Henry Lusvin Morales was charged with aggravated malicious wounding and felony child abuse.
Police were called to Morales' home Sunday night for the report of a child who was not breathing. Officers determined the 2-month-old had serious injuries.
The child remains hospitalized in critical condition with life-threatening head injuries, police said.
Morales is being held without bond.