North Korea denies hacking South's nuclear power operator

North Korea has refuted allegations it was involved in a recent spate of cyberattacks against South Korea's nuclear power operator, demanding Seoul produce evidence to back its accusations.

State-run Korea Hydro & Nuclear Power had experienced several hacking attacks over the past week, during which documents were stolen and operating manuals for nuclear reactors were published online. The incidents triggered concerns about the stability of the organization's network, which operates 23 nuclear reactors and powers one-third of the country's energy consumption, according to Yonhap News Agency.

Dismissing suggestions it was involved in the attacks, North Korea said such accusations were "a trumped-up plot against the communist country" and called for Seoul to provide proof before passing the blame to Pyongyang.

"South Korea is blindly trying to link the recent hacking of its nuclear power stations to us," said Rodong Sinmun, the newspaper operated by the North's ruling Workers' Party of Korea. "It is a totally groundless fabrication."

The Seoul administration and prosecution officials are investigating the cyberattacks, and have not ruled out North Korea's involvement, reported Yonhap, adding that a suspect was identified to have used multiple IP addresses originating from China.

Korea Hydro's CEO Cho Seok told local reporters its network remained secured and the hacking incidents had not affected its operations. Emergency teams also have been put on standby to address any potential attacks.

North Korea earlier denied any involvement in the attack on Sony Pictures, though it praised the security breach as a "righteous deed".

The cyberattack on the U.S. movie studio last month brought down its systems and leaked sensitive data including e-mail and confidential memos. The hackers said the attack was launched in protest of a film, "The Interview", which features a fictional story about two journalists recruited to assassinate Kim Jong Un, the leader of North Korea.

The U.S. Federal Bureau of Investigation had pointed to Pyongyang as the prime suspect in the cyberattack, saying it had "enough information to conclude" North Korea's involvement.