Commodities trader Trafigura Group, which is investigating a $577 million nickel fraud, extended an asset freeze to the alleged fraudster’s wife, saying in a London court that she is not a “wholly innocent bystander.”

Ginni Gupta, who lives in Dubai, faces the restrictions, after Trafigura’s lawyer argued that there is a risk her assets could be dispersed and put out of reach. Gupta, the wife of Prateek Gupta, is not herself a defendant in the company’s legal pursuit.

Trafigura in February accused Prateek Gupta and the companies connected to him of perpetrating a “systematic fraud” against it with details that have sent shockwaves through the metals industry. The trading house turned to the court after finding that nickel cargoes it had bought from him in fact contained no nickel. Gupta himself was hit with a $625 million freeze at the time.

The court hearing is a sideshow to the main proceedings, where Trafigura’s executives are waiting for Gupta to file his defense to their allegations.

Trafigura’s lawyer, David Peters, said Ginni Gupta’s assets extended to the family home in Dubai as well as Cayman Islands-based investment fund Silver Star SPC. Ginni Gupta has said in a Facebook video that she was the HR head of the family’s metal trading businesses.

Ms. Gupta is “not alleged to have committed any wrongdoing of any sort,” her lawyer Robert Howe said Friday. At the hearing, the judge dismissed his attempt to hold the proceedings in private.