By Fabio Teixeira RIO DE JANEIRO/SHANGHAI (Reuters) -Chinese workers at a construction site in Brazil for a factory owned by China's electric vehicle producer BYD are victims of human trafficking, Brazilian labor authorities said on Thursday in a growing controversy in BYD's biggest overseas market.

Brazilian labor authorities have accused Chinese electric vehicle company BYD and its contractor, Jinjiang Group, of human trafficking at a construction site in Bahia. The allegations highlight challenges in China's investment model and its relations with Brazil as BYD seeks to expand globally.

"Slavery-like conditions", as defined by Brazilian law, include debt bondage and work that violates human dignity. The MPT added that the situation also constitutes "forced labour", as many workers had their wages withheld and faced excessive costs for terminating their contracts. BYD said affected workers had been moved to hotels.