A lawmaker of the ruling Grand National Party denied opposition allegations Friday that he was behind an alleged cyber attack on the national election watchdog’s website during the recent by-elections.

Earlier in the day, police sought an arrest warrant for a chauffeur and secretary of Rep. Choi Koo-sik of the GNP on charges of attacking the website of the National Election Commission on Oct. 26.

“I don’t know anything about it. I feel like I’ve been struck by a bolt of lightning out of the blue,” the two-term lawmaker said at a press briefing at the National Assembly.

“If I’m found to have been involved in the (hacking), I will immediately resign as a lawmaker. I urge authorities to conduct a thorough investigation into the case to clarify the facts.”

The Cyber Force Center of the National Police Agency requested arrest warrants for four officials including the secretary, identified only by his surname Gong, for obstructing election procedures with distributed denial-of-service attacks on the NEC website.

According to police, Gong and three others mobilized more than 200 “zombie PCs” to generate heavy traffic ― 263MB per second ― on the NEC site, shutting it down for more than two hours.

A day before the by-election, Gong instructed a man named Kang in the Philippines to mount DDoS attacks, police said. Kang, and two others who were in Korea at the time, joined the attacks.

Police said they will investigate whether they sought to lower turnout among young voters who supported candidate Park Won-soon, current Seoul mayor.

Police will also examine whether Gong was involved in the shutdown of Park Won-soon’s personal website on Oct. 26.

By Kim Yoon-mi (yoonmi@heraldcorp.com)