The St. Petersburg Police Department said a man returned to his home Monday about 5:45 p.m. and discovered Corey James Earl Mathews, 22, standing near the residence while holding the 5-month-old baby in a car carrier.
Police said Mathews shouted to another man, later identified as Kenneth Floyd Tritt, 29, who was attempting to enter the home through a back door.
Tritt ran away from the scene and Mathews walked away with the baby, but the homeowner followed Matthews while calling 911.
Police said Mathews at one point stopped walking, set down the baby, and threatened the homeowner with a knife.
Mathews was stopped by police a short time later while still carrying the infant and he was identified by the homeowner.
Matthews was arrested on charges of residential burglary, aggravated assault, child neglect and violation of probation. The baby was released into the custody of Mathews' mother.
Tritt was arrested Tuesday and charged with attempted residential burglary.