Kamilo Sanders' 29-year-old mother, Alicia Fuentes, does not have custody of her son, according to the sheriff's department.
The boy was taken from a business located at 635 S. Atlantic Ave. about 8 p.m. on May 4, according to an LASD statement.
Fuentes left the location traveling in an unknown direction in a 2005 Infiniti FX35, California license plate 5SGY139, and is known to travel to Mexico, investigators said.
The boy is Hispanic, 3 feet tall and weighs 40 pounds, with brown hair and green eyes.
His mother is described as Hispanic, 5 feet 2 inches tall and130 pounds, with black hair and green eyes, according to the sheriff's department.
Anyone with information on their whereabouts was asked to call East Los Angeles Detective Rojas at 323-981-5006 or Detective Mendoza at 323-981-5044. Anonymous tips can be called in to Crime Stoppers at 800-222-8477 or submitted online at lacrimestoppers.org.