FBI agents raided two East Tennessee residences, including a Carson-Newman University dorm room, investigators say were hosting “laptop farms” used in a wide-ranging overseas identity theft scheme tied to North Korea.

Two search warrants unsealed Wednesday say the residences belong to two individuals, one a graduate student and one an undergraduate at Carson-Newman University. The students’ names are redacted in the indictment.

The search warrants assert the Jefferson City, Tennessee, laptop farms were part of a scheme allowing foreign technology workers to work for U.S. companies under the stolen identities of American residents.

A laptop farm is a “location hosting multiple computers all connecting to the internet through the same network, wherein individuals at the laptop farm assist remote individuals with logging on to the computers,” the search warrant says. This makes it appear like the remote individual is working at the laptop farm to avoid suspicion from their employer.

Between the laptop farms in Tennessee and one in California and another in Virginia, they hosted “approximately 79 computers,” the news release says. Agents raided the residences between May 8 and May 10, according to a news release from the U.S. Attorney’s Office.

The U.S. Attorney’s Office said that the scheme was run by a Ukrainian national, 27-year-old Oleksandr Didenko. The news release said Didenko operated U.S.-based online infrastructure and stole American identities so foreign workers could pay to market themselves as Americans. Some of the workers were in North Korea.

Running the scheme allowed Didenko to provide false identities to North Korean workers “in an effort to evade sanctions.”

Didenko was arrested in Poland on May, 7, and authorities are seeking his extradition to the U.S., the news release says.

Didenko has been charged with conspiracy to defraud the United States, conspiracy to commit wire fraud, aggravated identity theft, conspiracy to commit identity fraud, conspiracy to launder monetary instruments, operating as an unlicensed money transmitting business and unlawful employment of aliens. He faces up to 67.5 years in prison if convicted, the news release says.