The presidential office said Friday cyber attacks by pro-Russian hacking groups against South Korea have increased following North Korea's troop deployment to Russia in support of its war in Ukraine.

The National Security Council (NSC) held an emergency intra-agency meeting on Thursday after several government websites, including those of the defense ministry and courts, suffered distributed denial-of-service (DDoS) attacks earlier this week.

The NSC said the cyber attacks, mostly DDoS, by "pro-Russian hacktivist groups" have increased following North Korea's troop deployment to Russia.

"Although some government websites experienced temporary delays or disruptions, there has been no further damage," the NSC said in a release.

The National Intelligence Service is closely monitoring the activities of pro-Russian hacktivists and sharing information with relevant agencies to counter potential cyber threats, it said.