Taipower said there had been an incident with a transformer at the Hsinta power plant in the southern city of Kaohsiung, a major coal-fired station that provides around a seventh of Taiwan’s power. The incident caused an ultra-high voltage substation to trip, leading to the power failure.

Hydro and other power plants are being brought on line to provide electricity, Taipower said.

Parts of Taipei also lost power. The presidential office said President Tsai Ing-wen has ordered the government to investigate and restore power as soon as possible.

A livestream of Tsai’s meeting with the visiting former US Secretary of State Mike Pompeo in Taipei has been cancelled, it added.

The Hsinchu science park, home to many large semiconductor companies such as TSMC, said it was not experiencing power outages, and the Taipei city government said the mass transit system was operating as normal.

The southern Tainan Science Park, where TSMC also has plants, said it experienced a sudden drop of voltage in the morning, but that there was no impact on production.

Taiwan’s transport ministry said three trains on the high-speed rail line connecting northern and southern Taiwan were affected but normal service has now resumed.