MOSCOW (CBS SF/AP) — Ukrainian police say they have uncovered a ring of computer hackers responsible for cyberattacks that included targeting personal data and financial records at the Stanford University Medical School and the University of California.

Six members of the gang, known as Cl0p, were arrested and a number of computers, cars and about $185,000 in cash was seized.

The hackers also allegedly attacked four South Korean companies in 2019 with an encryption virus that blocked internal servers and employees’ computers.

Police video posted on Youtube shows Ukrainian police officers conducting many of the 21 raids, arresting individuals, seizing luxury cars and counting stacks of $50 and $100 U.S. dollar bills.

The alleged Stanford breech was part of a larger national cyberattack on universities and organizations revealed in April 2021 that used a 20-year-old file transfer appliance to gain access to the medical school’s database, the university said in a statement.

“Stanford University School of Medicine has learned that cybercriminals have claimed they have stolen some School of Medicine data. … We are investigating this incident and we have reported the incident to law enforcement,” the university said at the time.

It has not been revealed if either Stanford or UC officials paid a ransom to the group.