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.

Brazil has stopped issuing temporary work visas for BYD, the Brazilian Ministry of Foreign Affairs said on Friday, in the wake of accusations that some workers at a site owned by the Chinese electric vehicle producer had been victims of human trafficking.

BYD has been building the factory with an annual capacity of producing 150,000 cars initially in Brazil, the Chinese EV giant's largest overseas market, as part of plans to start production there.