KYIV, June 16 (Reuters) - Ukrainian police said on Wednesday they had uncovered a group of hackers who had carried out ransomware attacks on foreign companies and universities between 2019 and 2021. Six hackers had targeted the servers of U.S. and South Korean companies, threatening to disclose confidential data if the victims did not pay up, according to a police statement. The total damage inflicted amounted to $500 million, the police said. A total of 21 searches on the homes and the vehicles of the alleged hackers were conducted police said. They did not say whether any of the suspects had been detained.