A fishing boat is crushed when a bridge collapsed in Nanfangao harbor in Taiwan on 1 October 2019. (AFP)

The head of an agency that oversees a steel arch bridge that collapsed Tuesday in northeastern Taiwan, killing six people, resigned on Thursday.

Transportation minister Lin Chia-lung told a legislative committee that Taiwan International Ports Corp. failed to check the cables of the steel arch bridge that collapsed Tuesday at Nanfangao, a fishing township in Yilan County.

“Company chairman Wu Chung-rung should be held responsible,” Lin said. “As for who will be his successor, we’ll think about it later.”

The company is a state enterprise owned by the ministry.

Lin said he has asked the company to conduct a wholesale examination of the 16 bridges under its supervision and complete a report within three months, as well as to propose a plan to ensure the safety of those bridges.

The Nangfangao Bridge, completed in 1998, was reinforced in 2017 and again last year. It was last examined in 2016 and was scheduled for another checkup next year.

The bridge collapsed around 9:30 a.m., killing three Filipinos and three Indonesians who were working on two Taiwanese fishing vessels that were crushed.

Twelve others were injured, including nine foreign crewmen and the driver of an oil tanker truck that had traversed the bridge driven over the span and almost reached the other side when it suddenly gave way.

Video footage showed the bridge suffer a catastrophic failure and plunge into the water below, smashing three fishing boats underneath.

President Tsai Ing-wen has ordered the transportation ministry to investigate the cause, vowing her government will not shirk its responsibility.

The Taiwan Transportation Safety Board expects to complete its investigation report within 10 months, while the Yilan District Prosecutors Office has kicked off its own investigation. (Kyodo)