According to Rialto Police, a woman and her boyfriend were scheduled to meet a Child Protective Services representative at a McDonald's restaurant in Rialto. They arrived for a supervised visit with the woman's two children, a 2-year-old and a 6-month-old.
The couple allegedly fled the scene with the 2-year-old, Elijah Cardenas, while the CPS representative was putting the infant in a car seat. They drove away in a black Dodge SUV.
Police said the child was found and Stacey Nicole Patterson, 21, and James Krost, 53, were arrested later Wednesday night.
Earlier, an Amber Alert was launched for San Bernardino, Riverside, San Diego and Orange counties.
Anyone with information about the case should contact the Rialto Police Department at (909) 820-2596.
The mother had her two children originally taken away from her due to a corporal punishment incident involving the children.