The Taiwanese government said on Wednesday it launched a probe into a massive blackout that affected millions of households on the heavily industrialized island one day earlier.

President Tsai Ing-wen apologized for the massive blackouts that hit late on Tuesday, leaving homes, offices and shopping malls and traffic in darkness amid temperatures that reached 32 degrees Celsius (89.6 F).

"I, on behalf of the administration, deeply apologize for the inconvenience and worry caused. It should not have happened," Tsai said at a meeting of her ruling Democratic Progressive Party's Central Standing Committee in Taipei.

She also called for a thorough review of the country's "fragile power supply systems."

The outages appeared to be over by Wednesday afternoon, with power fully restored on the island of 23 million people and Taiwan's leading technology manufacturers up and running again.

Human and 'structural' error

Taiwan's economy minister Lee Chih-kung resigned later on Tuesday over the crisis, which stemmed from a generator failure at the Tatan Power Plant, the largest natural gas facility in Taiwan.

The blackout was caused by "structural problems" and human error that occurred during the replacement of equipment, said the state-owned gas supplier CPC Corporation Taiwan.

Taiwanese Premier Lin Chuan on Wednesday ordered a probe to identify possible management problems in the CPC and the state-run Taiwan Power Company.

The malfunction cut power to an estimated 6.68 million households and in 17 cities and counties, including the capital, Taipei, as well as Taichung and Tainan.

Tuesday's blackout was the country's most severe since the 1999 Jiji earthquake, Taiwan Power Company said.

rs/kms (AP, dpa, Reuters)