Prosecution investigators raided the office and home of a former top aide to former President Lee Myung-bak on Tuesday as part of an investigation into allegations that the military’s cyberwarfare command attempted to interfere with the 2012 presidential election.

Kim Tae-hyo, a Sungkyunkwan University professor who served as a senior secretary to Lee, is suspected of involvement with the cyber command‘s operations to write Internet comments to sway public opinions in favor of the then-ruling party’s candidate Park Geun-hye.

Park ultimately won the election against opposition candidate Moon Jae-in, though she was removed from office earlier this year due to a massive corruption scandal involving one of her longtime friends. Moon succeeded her after winning the presidential election in May.