S Korea's Park says leak of nuclear plant data a "grave situation"

SEOUL - South Korean President Park Geun-hye said on Tuesday the leak of data from the country's nuclear operator was a "grave situation" that was unacceptable as a matter of national security.

"Nuclear power plants are first-class security installations that directly impacts the safety of the people," Park said at a cabinet meeting, according to her office.

"A grave situation that is unacceptable has developed when there should have been not a trace of lapse as a matter of national security," she said.

Earlier, a South Korean official said Seoul had not ruled out the possible involvement of North Korea in the cyberattack on South Korea's nuclear power plant operator, although Park did not make any mention of it.