HONG KONG (AP) — Hong Kong police are investigating allegations that a 23-year-old Indonesian maid was tortured by her employers, the latest case to provoke outrage over abuses suffered by the city’s army of foreign domestic workers.

The Hong Kong chapter of Indonesia’s migrant workers union says Erwiana Sulistyaningsih came to the city in May and suffered beatings until returning home this month. She’s currently being treated in a hospital.

The union’s vice-chair, Sringatin, said Thursday that the family that employed Sulistyaningsih slapped and punched her every day. Sringatin said the employers let her go home after she could no longer work because of her injuries. Like many Indonesians, Sringatin uses one name.

Police said they were investigating.

Migrant worker groups have protested this week to highlight what they called “modern day slavery.”