Police are searching for a young Bronx boy who they say was taken by his biological mother in the middle of a custody battle.

According to cops, Justin Branch was last seen Jan. 20 while getting into a cab with 34-year-old Yanick Branch before school at P.S. 130 on Prospect Avenue. The 10-year-old is in the legal custody of a foster mother who lives on Union Avenue.

Authorities describe Branch as about 4 feet 8 inches tall with black hair. They urge anyone with information on the whereabouts of either person to call Crime Stoppers at 1-800-577-TIPS.