Authorities say a New York City woman kept two South Korean children as slaves in her home for six years.

District Attorney Richard Brown says Queens resident Sook Yeong Park took the sister and brother into her home in 2010 and cut off contact with their parents. The children are now 14 and 16.

Brown says Park seized the children's passports, forced them to do household chores into the night and made them work at a grocery store and turn their earnings over to her.

Park was arraigned Saturday on charges of labor trafficking, assault and endangering the welfare of a child. Her attorney did not immediately return a call.

Brown says the abuse came to light when a high school assistant principal noticed bruises on the girl's legs.