Brazilian prosecutors are suing Chinese electric vehicle (EV) giant BYD and two of its contractors, saying they were responsible for human trafficking and conditions “analogous to slavery” at a factory construction site in the country.

The Public Labour Prosecutor’s Office (MPT) in the state of Bahia says 220 Chinese workers were rescued after it began an investigation in response to an anonymous complaint.

The MPT is seeking 257 million Brazilian reais ($45.5m; £33.7m) in damages from the three companies.

BYD did not immediately respond to a request for comment from the BBC but has previously said it has “zero tolerance for violations of human rights and labour laws.”

Authorities halted construction of the plant late last year after workers were found living in cramped accommodation with “minimum comfort and hygiene conditions”, the MPT said.

Some workers slept on beds without mattresses and one toilet was shared by 31 people, it said in a statement.

The MPT also alleged that construction site staff had their passports confiscated and were working under “employment contracts with illegal clauses, exhausting work hours and no weekly rest.”

Prosecutors said the workers had up to 70% of their salaries withheld and faced high costs to terminate their contracts.

“Slavery-like conditions”, as defined by Brazilian law, include debt bondage and work that violates human dignity.

The factory was being built in the city of Camacari in the north east of Brazil.

It was scheduled to be operational by March 2025 and was set to be BYD’s first EV plant outside of Asia.

BYD, short for Build Your Dreams, is one of the world’s largest EV makers. In April, it outsold Elon Musk’s Tesla in Europe for the first time, according to car industry research firm Jato Dynamics.

The firm has been looking to increase is presence in Brazil, which is its largest overseas market.

It first opened a factory in São Paulo in 2015, producing chassis for electric buses.