Authorities in Brazil said Friday they were probing Chinese auto giant BYD and one of its contractors for suspected “trafficking” of Chinese workers who were building a factory in the South American country.

Brazil has stopped issuing temporary work visas for BYD , the 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.

Announcement came days after labour authorities also said they found Chinese workers at factory in Bahia were victims of human trafficking.