The high-profile case involves claims two intelligence agents illegally intervened in politics by posting numerous politically sensitive comments on the Internet prior to the Dec. 19 presidential elections, South Korea's Yonhap News Agency reported Friday.
The Seoul Central District Prosecutors' Office said it assembled a team of investigators to review records.
The action comes amid mounting public criticism that police have not fully explained suspicions the intelligence agency intervened in the election, Yonhap said.
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