A US federal lawsuit has alleged that a Malaysian diplomat and his wife made their Sri Lankan domestic helper work more than 15 hours a day for below minimum wage at less than US$1.71 hourly.

US paper the New York Post reported that the couple — Arasi Krishnan and her husband Danish Kumar — also forbade Parimaladevi Jeganathan from leaving their luxurious East 43rd Street apartment in New York City and allegedly warned her that “black people” would “do something to her” if she did, according to the Manhattan federal lawsuit.

“It was pretty clear that she was their servant. She wasn’t allowed to leave the house except to sometimes accompany the family to church,” Anne Li, Parimaladevi’s lawyer, was quoted saying.

The US State Department reportedly listed Arasi as a consul at the Malaysian consulate on East 43rd Street.

The Manhattan federal lawsuit reportedly accused the Malaysian couple of violating laws on the protection of human trafficking victims. It also accused them of breaking state and federal labour laws and slapped the couple with civil charges of fraud and of breach of their contract with Parimaladevi.

Court papers reportedly stated that Parimaladevi started working for Arasi and Danish in 2013 and had arrived in the United States in March that year.

The lawsuit claimed the Sri Lankan woman believed that while she was working as a “do-it-all” domestic helper for the couple, she was monitored by their building’s doorman and by Malaysian consulate security guards.

Parimaladevi was “fearful of venturing outside alone”, according to the lawsuit.

Arasi allegedly told Parimaladevi early in 2014 that her visa had expired and it was too expensive to renew. The employer reportedly said if Parimaladevi didn’t agree to work for her for another three and a half years, she would be forced to go back to war-torn Sri Lanka.

“She was frightened…and worried for her family,” Parimaladevi’s lawyer Li was quoted saying.

The Sri Lankan then contacted the US Federal Bureau of Investigation (FBI) who took her from the apartment on March 6, 2014. She is reportedly staying in New York City at a safe house now.

According to Li, no criminal charges were filed against the couple who are back in Malaysia.