Portland, Ore. ? Authorities said nine people were arrested Thursday as investigators broke an international sex-trafficking ring that smuggled Asian women into the U.S. in shipping containers.

Seven conspirators in a “highly organized national network prostitution ring” were arrested in Seattle and two in Los Angeles, the U.S. attorney’s office said.

According to court documents, Yong Jun Kang, 36, of Seattle, operated brothels in Portland, Ore., and Seattle, where he and others would bring Asian women, most of whom were in the United States illegally.

Authorities allege that Kang told confidential informants that women were being smuggled into the U.S. in shipping containers after paying as much as $50,000. Some of the women, investigators said, were brought into the United States by crossing the Canadian border.