According to police, the baby was left alone in a Riverside County apartment when the attack happened.
The mother, 22-year-old Carrie McKinney, left her child in the carrier on the floor in her friend's apartment. Police say that is when the pit bull and pit bull mix attacked the baby, tearing off the infant's diaper and biting his scrotum.
After hearing the baby scream, the mother and a friend rescued the child. He was hospitalized, but his condition is unknown.
Police and child protective services are investigating, but no charges have been filed. The dogs are being euthanized.
The Associated Press contributed to this story.