The locations also included the office of an organization comprising retired NIS officials as well as the office of a conservative civilian organization made up of supporters of former President Lee Myung-bak, they said.

Prosecutors have also banned the 30 team leaders as well as former and incumbent NIS officials suspected of involvement in the scheme from leaving the country. Investigators are tracing bank accounts to track down the money flow between the agency and the secretive teams.

Depending on the results of the investigation, prosecutors could press additional charges against then NIS chief Won Sei-hoon. Won is on trial for allegedly pulling the strings of the cyber operations to help then-conservative candidate Park Geun-hye.

Another focus of the probe is how far it will go, including who else, in addition to the former NIS chief, will be investigated. Some even speculate that top officials of the government of then President Lee could be targets. (Yonhap)