A man living in Toronto accused of recruiting women from China to engage in the sex trade now faces extradition to the United States following an international investigation involving the FBI.

Mark Chen, 46, also known as Zongtao Chen, is accused by U.S officials of heading a criminal organization that recruited women, most of them from China, to work overseas in a multi-city prostitution ring.

The U.S. federal government has ordered that Chen be extradited to face indictments in Oregon.

According to the FBI, the prostitution ring operated in the U.S. and elsewhere, and involved a “boss” overseeing brothels run out of hotels and apartment complexes.

The FBI reached out to Toronto’s Human Trafficking Enforcement Team, which located the accused living in the Greater Toronto Area.

Chen was arrested Tuesday in a “multi-jurisdictional take down operation,” Toronto police said in a press release. He appeared in court on Wednesday in regards to the extradition order.

Toronto police launched their own investigation into Chen “regarding human trafficking related offences that have taken place in Toronto.”

According to U.S. authorities, the operation relied on a number of so-called “dispatchers” who arranged “dates” between sex workers and customers. A computer program used to coordinate these “dates” logged more than 30,000 phone numbers from past customers, officials said.

Police are concerned that there may be more victims and have asked that anyone with information contact the Toronto Police Service Human Trafficking Enforcement Team.

“We want to make sure that everyone has access to support services and an exit strategy, regardless of their decision to proceed criminally,” police said in a statement.