Nicholas Johnston, 12, and his mother, 49-year-old Sri Johnston, were found in Oceanside at 2:40 p.m., nearly two hours after the Amber Alert was issued, according to the Long Beach Police Department.
Prosecutors announced Monday afternoon they filed kidnapping and child custody deprivation charges against Sri, who is accused of picking up Nicholas on March 5 for visitation and not taking him to school the next day, according to the Los Angeles County District Attorney's Office.
She was taken into custody by US Marshals and is due in court this week. If convicted, she faces a maximum sentence of 13 years and 8 months in prison.
Nicholas was expected to be reunited with his father sometime Monday, Long Beach police said.
California Highway Patrol officials said he was abducted on March 6, and they do not know why the Amber Alert was not issued for four days.
Sri Johnston may have been driving a tan 1998 four-door Saturn with a California license plate #4AUU679. Details about how they were located were not immediately clear.
Anyone with information is asked to call the Long Beach Police Department at 562-570-9650.