An unseasonable heat wave caused power outages around South Korea on Thursday, trapping hundreds of people in elevators, shutting down traffic lights and stopping factory operations.
The outages were reported in Seoul and other major cities and affected at least 820,000 homes across the country for about six hours until power was restored, local media reported.
Economy Minister Choi Joong-kyung apologized in a statement for failing to be adequately prepared for the surge in demand. Officials said demand was 3.2 million kilowatts higher than expected.
Thursday's temperature of 88 degrees Fahrenheit in Seoul was the highest in nearly two weeks. The state-run Korea Power Exchange, which coordinates power supplies, said that some power facilities were being repaired when the demand for power peaked.
The ministry said it was still assessing damage from the outages. Lee In-sun, an official at the National Emergency Management Agency, said nearly 1,000 cases of people being trapped in elevators were reported. No injuries or deaths were reported from the outages, he said.
Broadcaster YTN said cellular phones stopped working and traffic lights went out in some areas of the country. It said some factories also stopped work because they lost electricity. Major companies like Samsung Electronics, Hyundai Motor and POSCO were not affected, it said.
Yonhap news agency said a professional baseball match in Seoul was stopped for an hour in the evening because of a blackout. It also said bank operations were briefly suspended in the southeastern port city of Busan.